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ATSDR

Agency for Toxic Substances and Disease Registry

PUBLIC HEALTH ADVISORY TRINITY AMERICAN CORP., GLENOLA INDUSTRIAL DRIVE

RANDOLPH COUNTY, NORTH CAROLINA

October 20, 1997

U.S. Department of Health and Human Services Agency for Toxic Substances and Disease Registry Division of Health Assessment and Consultation Atlanta, Georgia 30333

EXECUTIVE SUMMARY

The Agency for Toxic Substances and Disease Registry (ATSDR) is issuing this public health advisory to notify the U.S. Environmental Protection Agency; the National Institute for Occupational Safety and Health; the State of North Carolina Department of Environment and Natural Resources; the Randolph County Health Department; and the public of the Glenola community in Randolph County of ATSDR's concerns regarding potential adverse impacts on the health of residents living near the Trinity American Corp. (TAC) facility on Glenola Industrial Drive in Randolph County, North Carolina. TAC is the parent company of Trinity Foam of Carolina, Inc. and Trinity Fibers of Carolina, Inc.

 

 
The Polyurethane Foam Association's Critique
 

In the interest of accuracy and fairness, the Polyurethane Foam Association asked a number of experts for comments on the Public Health Advisory for Trinity American Corporation. The following is a compilation of the experts' comments.

 

 

 

 

 

 

 

 

Data and information obtained and reviewed by ATSDR strongly suggest that hazardous substances are being released into the air and possibly into other environmental media as a result of operations at the TAC facility, and that these hazardous substances are impacting residential areas at levels that may pose a significant risk to human health.

Furthermore, ATSDR believes that substantial releases of hazardous substances into the environment have occurred in the past and that environmental media other than air may have been contaminated.

The ATSDR states that data "strongly suggests" that hazardous substances are being released into the air and "possibly into" other environmental media, and they "may pose" significant risk to human health. The three phrases are not scientific. Does this agency deal with facts and data or speculation? Does the data indicate hazardous substances are being released or not? What does "possibly into other environmental media" mean? Are these substances posing a significant risk to health or not?

ATSDR is concerned that residents are being exposed to toxic substances such as 2,4- and 2,6-toluene diisocyanate (TDI) and other isocyanates known to exacerbate or cause obstructive airway disorders and sensitization reactions.

ATSDR is also concerned that residents are being exposed to other air contaminants that have been measured at levels of health and safety concern but have not been identified.

Until the contaminants are identified, they cannot be measured at levels of health and safety hazards, nor can the source be determined.

During plant operations, the local residents report intermittently experiencing headaches, dizziness, rashes, throat irritation, and chest tightness that are temporally correlated with the detection of odors and elevated levels of unidentified substances measured in off-site air.

 

Unidentified substances measured at elevated levels "not quantified" are the cause of all the ailments?

ATSDR and other agencies are concerned about chemical exposures of workers within the TAC facility as well as exposures of local residents.

 

This is also a primary concern of PFA, and we encourage a thorough scientific investigation of the situation and careful examination of the plant workers and neighbors by specialized physicians and toxicologists familiar with the specific chemicals being used at the Trinity foam plant.

ATSDR issues a public health advisory for sites to human health where a release or threatened release of hazardous substances may pose a serious threat . The agency uses the following criteria to determine the need for an advisory:

  1. Hazardous materials on a site are known to be toxic to human health, or physical conditions exist that may pose a serious threat to public health.
  2. An established or plausible exposure pathway exists between the contaminant and the nearby human population.
  3. People are being or could be exposed to hazardous substances at levels that pose either an urgent public health hazard or a public health hazard.
  4. There are no plans for immediate remediation or removal.
  5. The public health advisory is ATSDR's best option for ensuring a rapid response to safeguard public health.

INTRODUCTION

This public health advisory is to notify the U.S. Environmental Protection Agency (EPA); the National Institute for Occupational Safety and Health (NIOSH); the State of North Carolina Department of Environment and Natural Resources (DENR); the Randolph County Health Department; and the public of the Glenola community within Randolph County of an ongoing public health hazard.

The public health hazard is associated with the past, current, and potential future exposures to hazardous air pollutants emitted from the Trinity American Corp.

(TAC) foam and fiber facility on Glenola Industrial Drive in Randolph County. The Agency for Toxic Substances and Disease Registry (ATSDR) is issuing this public health advisory in response to requests for assistance from the DENR, the Randolph County Health Department, and the Glenola community.

 

  The meaning is not understood. The criteria to determine the need for an advisory are ambiguous, and not quantifiable. Essentially it appears an advisory can be issued based on spurious uninvestigated or unproven complaints.

ATSDR has concluded that the presence of hazardous substances in the community's ambient air warrants this public health advisory [1, 2, 3].

 

  The results of the detection and monitoring activity to support this conclusion have not been released to the knowledge of the PFA.

Unidentified volatile organic compounds (VOCs) and semi-VOCs have been detected in the air and are assumed to be at levels of public health and safety concern [4].

 

  PFA is not familiar with substance categories "unidentified VOCs" and "semi-VOCs."
What is the basis of the assumption? Should an assumption without a factual basis serve as evidence for a public health advisory?

Compounds such as isocyanates; methylene chloride; 1,1,1-trichloroethane; acetone; benzene; ethylene oxide; formaldehyde; and other VOCs have been identified in the ambient air at levels that may pose a serious threat to public health [3, 5].

 

The National Contingency Plan (40 CFR Part 300.400-420) describes the types of activities required and authorized in response to a hazardous substance release at a potentially hazardous site. Activities include notification of a release (Section 300.405(f)(1)); evaluation of the site (Section 300.410); and factors to be considered related to a removal action (Section 300.415). These factors include the migration of contaminants, the threat of fire or explosion, and other events that could threaten public health.

Based on the review of the available information, ATSDR recommends the use of statutory, regulatory, or administrative authorities as appropriate to protect the public's health and to characterize these exposures further. Specifically, ATSDR recommends that appropriate agencies take the following actions:

 

  Here VOCs are identified. The report states above that the VOCs are "unidentified." If they are truly identified, which VOC compounds were found and at what levels of concentration?
Furthermore, it is essentially impossible for acetone to be detected in the ambient air at "levels that may pose a serious threat to public health."

1. Use their statutory, regulatory, or administrative authorities to implement measures that will immediately reduce or eliminate opportunities for residential exposures to hazardous substances emitted from the TAC facility.

2. Conduct environmental sampling as appropriate (air, private well water, surface water, surface soil, and biota) to facilitate qualitative and quantitative estimates of residential exposures under a variety of scenarios.

  TAC advised PFA that carbon scrubbers were installed after the ATSDR/EPA monitoring activity and prior to the release of the October 20, 1997, Public Health Advisory. Scrubbers would substantially reduce stack emissions.

3. Investigate the TAC facility and interview employees to assess occupational exposures.

4. Provide local health care providers and public health officials with necessary information on the diagnoses and treatment of symptoms and health effects associated with environmental exposures to the specific chemicals and classes of chemicals identified.

 

  TAC advises that it operates under the exposure limits established by OSHA.

5. Conduct biomedical testing (analyses of blood) for biomarkers of exposure to TDI and other isocyanates among residents and TAC employees.

6. Consider conducting studies (including biomarkers of effect) for the prevalence of various chemical exposure-related health effects among residents and TAC employees.

BACKGROUND

Site Location and History

In 1981, the TAC facility began operations at 5275 Glenola Industrial Drive in the unincorporated community of Glenola, Randolph County, North Carolina [6]. The site consists of 15.7 acres used for the production of fiber padding and the production and fabrication of foam for the bedding and furniture industries. Four primary operations occupy the site: a fiber production facility, a polyurethane foam production facility, a warehouse, and a tenant's business (Guilford Fabricators). Thomasville Products (foam manufacturer) owned the property from 1973 to 1981. The site was undeveloped before that time [6].

 

  A number of physicians who specialize in worker exposure to isocyanates question whether reliable biomarkers exist.

Processes at the Foam Facility

Polyurethane foam is manufactured by reacting a resin, typically a polyether such as polyoxypropylenetriol, with TDI and water.

Small quantities of an emulsifying agent, a polymerization catalyst, and a silicone lubricant are also added [7]. For certain higher quality grades of foam, methylene chloride (MeCl) is used as a blowing agent [7].

  Although not critical to the conclusions offered, the process described is inaccurate and not representative of the systems and chemistry employed at TAC.

For fire retardant foam, a tin catalyst is added.

The ingredients are mixed and deposited onto a moving conveyor, and the polyoxypropylenetriol resin and the TDI polymerize and cross-link to form the urethane resin in the shape of a continuous foam-like structure called a loaf [7].

The loaf dries in a cooling chamber, where exhaust fans draw off chemical emissions for 20 to 30 minutes. These emissions peak during the first 2 minutes of the blow-off, when pressure inside the foam bubbles exceeds the pressure outside [7]. The foam continues to off-gas rapidly for the next 5 to 10 minutes [7].

  Not true.

After this period, off-gassing becomes diffusion controlled. Emissions are directed to stacks, which direct them to the ambient air; no emission controls are in place.

The manufacturing processes at the foam facility occur in batches which result in episodic releases of emissions.

Processes at the Fiber Facility

The TAC fiber facility processes scrap fibers in the manufacturing of Spansadeck fiber insulator pads for the bedding and furniture industries [5]. ATSDR is gathering data on the specific processes and engineering controls used in this operation.

Demographics

Glenola is an unincorporated community in Randolph County, North Carolina. The 1990 U.S. Census listed the county population as 115,548 people [8]; approximately 500 of these people live in Glenola. Approximately 1,650 people live within a 1-mile radius of the TAC facility. This population includes 162 children less than 6 years old and 120 adults more than 65 years old [8].

Reported Heath Effects

 

 

This is not true. Scrubbers are in place.

Since June 1997, ATSDR has received more than 200 telephone calls from residents near the TAC facility. The residents have reported a number of symptoms, including dizziness, breathlessness, headaches, nausea, loss of memory, flushing of the face and neck, fatigue, lethargy, sleeping difficulties, and difficulty breathing. They report a significant reduction of symptoms after leaving the area near the facility. The health effects described during these telephone calls are similar to those described by residents in one-on-one sessions with ATSDR staff during a public availability session in May 1997 [9].

Personnel from the State of North Carolina Air Toxics Analytical Support Team have been conducting air sampling near the TAC facility since January 1995. While conducting sampling activities near the TAC facility, these personnel have at times reported symptoms similar to those described by the residents [10].

 

These statistics are imprecisely stated. Were there 200 telephone calls by 200 different individuals or from 10 individuals who called 20 times each? We have been unable to find out whether the agency made a record of the names, times, and dates of the calls. What was the operating status of TAC at the times the calls were received?

Were these calls, in fact, from the same individuals who attended the public availability session?

     

 

Furthermore, ATSDR employees have been conducting air sampling near the TAC facility since May 1997 and have at times reported similar symptoms and observations of a visible plume during episodic events [11].

Environmental Monitoring

  PFA has several questions concerning this air sampling. Was there a correlation established between "visible plume," reported complaints, and foam production operations? The ATSDR employees were presumably close to the production site. Employees would be much closer. Are there reports of ill effects from TAC employees at this time? Was the plume tested and its composition identified?
Environmental monitoring to date has detected TDI, hexamethylene diisocyanate (HDI), MeCl, and total hydrocarbons in the community's air. ATSDR has identified a completed exposure pathway for TDI and other volatile and semi-volatile organic compounds at levels that may pose a serious threat to public health in areas around the TAC facility.   HDI is never used in foam production nor is it a by-product of any chemical reaction in foam making. Hydrocarbons, other than possible trace amounts of benzene, would not be emitted from a foam plant.
During an ATSDR/EPA environmental sampling event, residents contacted sampling personnel at approximately 10 pm on August 11 to indicate that strong odors were present and that they were experiencing adverse health effects similar to those previously reported.  

During the events of August 11 and September 3, which units at TAC were operating that late in the evening?

EPA and ATSDR personnel confirmed the presence of the strong odors and a visible plume of material in the ambient air.   Was foam production taking place at this time? Where did the plume originate, from the foam plant or other facilities?

EPA personnel had two flame ionization detector monitors (FoxboroTM organic vapor analyzers, or OVAs) to monitor the ambient air for volatile organic vapors . EPA personnel had calibrated those screening instruments when they arrived in the site area on the morning of August 11.

  By definition, flame ionization destroys the vapors detected and can only give a total number with no identification. There is no indication as to what method was used to identify the listed products. Confusion about amounts before and after calibration (from the draft report) still exists. There is no report of checking for emissions either upwind from the plant or at a time when there are no reported emissions.
At approximately 10:00 pm , August 11, the OVAs detected total volatile organic compounds in the ambient air at the residential location at levels from 2 to 6.2 units, or parts per million (ppm). The 2 OVAs were then recalibrated (with methane) at an upwind location. After recalibration, OVA instrument readings were as high as 2.5 units (ppm). OVA readings remained elevated (greater than 1.0 unit [ppm]) for several hours. EPA and ATSDR personnel continued to monitor using the OVAs until approximately 1 am on August 12 [5].   The implication that the contaminants detected by the OVA were coming from the foam curing facility is made by indication of the increasing concentrations with proximity. Even a two-dimensional dispersion should show a more rapid decrease of the concentrations from 100 ppm than those reported. The identity of the contaminant in the curing area should have easily been determined as the blowing agent.

A few weeks later (approximately 10 pm on September 3), an environmental scientist and an environmental engineer from the North Carolina Department of Environment and Natural Resources (DENR) observed the following OVA readings:

  1. From 3.5 to 5 ppm in the community air
  2. From 5 to 10 ppm at the fenceline of the TAC facility;
  3. Up to 100 ppm inside the foam curing facility.

Based on these concentrations of unidentified contaminants, ATSDR recommended

  The data shows high readings outside and up to 100 ppm in the curing area. The outside readings should be stated as to how far away, at what level above ground and the wind conditions at the time, etc. This is normally expected for any outside monitoring data and is required for any of the available computer dispersion models. Certainly, if the product measured is methylene chloride (easily confirmed by TAC), then there are monitors available to measure that specific chemical.

implementation of the Glenola Community Contingency Plan. The local fire department initiated voluntary evacuation of individuals living in 107 homes within a 1/4-mile radius of the facility and of facility employees.

On September 3, 1997, the State Health Director issued a public nuisance order directing the TAC facility to cease all manufacturing (foam and fiber) operations. State health officials indicated that the facility will remain closed until TAC can demonstrate that the operations are no longer a public nuisance [12].

  This activity appears to have been dramatically staged at 2:00 a.m., although readings were made at 10:00 p.m. on the previous day.
ATSDR has conducted air monitoring and confirmation sampling in residential areas near the TAC facility to quantitate ambient air TDI concentrations resulting from foam production. ATSDR used tapemeters with diisocyanate-specific chemcassettes and the TDI calibration program to monitor for TDI on a continuous realtime basis during these short release periods [13]. Results from a confirmation sampling methodology that speciates and specifically identifies each of the isocyanates have confirmed the presence of TDI and HDI in the community's air [14, 15, 16]. Analysis of air samples collected using the confirmation methodology have confirmed the presence of TDI and HDI in short-term air samples (2-45 minutes) [16]. Because the efficiency of isocyanate capture on the sampling device used in the confirmation methodology is low, measured concentrations may underestimate the actual air concentrations [14, 15, 16].
  A previous draft report indicated negative identification for any isocyanates. The confirmation methodology is not specifically identified. Six of thirty samples show TDI and nine of twenty samples show HDI. The concentrations reported indicate that these could not have come from tape data, because they are too low to be measured that way. The relationship between micrograms per cubic meter and parts per billion is 7.2 for TDI and 6.8 for HDI. Based on that, the TDI concentrations shown are .00036 to .025 ppb, which is considerably below the detection limit for tapes and significantly below any reported health effect data. For HDI, the corresponding data is .007 to .066 ppb. Again, there is no data as to where or when the samples were taken, including the ones which showed no TDI or HDI. Tape meters cannot detect TDI below 1 ppb.

This conclusion cannot be supported.

Thirty confirmation air samples were collected and analyzed for TDI; TDI was detected in 6 samples at concentrations ranging from 0.0026 to 0.18 g/m3.

Biological Monitoring

DENR has entered into an agreement with Duke University's Department of Occupational and Environmental Medicine to provide high quality standard clinical evaluations of residents reporting health symptoms thought to be associated with exposure to environmental contaminants. Duke University has begun clinical evaluations of certain residents within the air-shed of the TAC facility who have reported adverse health effects consistent with exposure to these substances.

 

The "confirmation" of the presence of TDI in the community air is highly suspect for two reasons:

  1. All the levels reported are below the limit of detection (LOD) for the method as given in ASTM D5932, Standard Test Method for Determination of TDI in Air (with MAMA) in the Workplace. This method covers the use of the cassette technology cited. D5932 gives a LOD for TDI of 0.28 mg/m3 (=280 ug/m3) with 15 L sample volume whereas the advisory reports TDI levels of 0.0026 to 0.18 g/m3 - 1000 times less than the LOD. D5932 also sites validation of the method down to 0.02 ug of 2,4-TDI and 4.2 ug of 2,6-TDI. If ATSDR used a standard 1 L/min air sampling rate, the maximum sampling time of 45 minutes would collect only a total of 0.008 ug TDI (both isomers) for the minimum reported concentration - at least 10 times less than the validated LOD.
  2. A description of the methodology for confirming TDI in "short-term air samples" is not given in reference #16. This misstatement raises doubt about the thoroughness and reliability of the rest of the advisory; in other words, this is "questionable science."

Thirty confirmation air samples were collected and analyzed for TDI; TDI was detected in 6 samples at concentrations ranging from 0.0026 to 0.18 µg/m3.

  The presence of HDI was also reported in the advisory and "confirmed." The very low levels of HDI reported, although higher than the reported TDI, may also not be at a validated level. HDI is not used in slabstock foaming. Additionally, HDI has very low volatility (bp of 101o C at 0.5 mm Hg pressure) and would not be expected from any source except a mist, which should have been reported as such from the collection method used.

These clinical evaluations being conducted by Duke University include analysis of blood samples for the presence of antibodies that are produced by the body as a result of exposure to TDI. These TDI antibodies (Immunoglobulin G (IgG) and Immunoglobulin E (IgE)) are produced as a specific response to TDI exposure. Exposure to other chemicals will not result in production of TDI-specific antibodies. The analysis of the blood samples uses an enzyme-linked immunosorbent assay (ELISA) [17]. The ELISA tests are both very sensitive (most individuals with TDI-specific antibodies test positive) and very specific (most individuals without the TDI-specific antibodies test negative) [18].

However, the ELISA test cannot be considered a sensitive biomarker for exposure to TDI, because many individuals exposed to TDI do not develop these antibodies. Only 14% of TDI-exposed individuals in occupational settings exhibit the presence of TDI antibodies [19]. In nonoccupational settings, exposure to significant levels of TDI (i.e., TDI levels that would cause health effects or production of TDI antibodies) is very rare, because the compound is very volatile (dissipates rapidly into the air) and very reactive (reacts readily and breaks down with other substances).

 
The presence of TDI antibodies does not necessarily indicate an adverse health effect, nor does it necessarily mean you have been exposed to TDI. The test for TDI antibodies is neither simple nor completely accurate. Some individuals test positive, regardless of whether they have been exposed to TDI or not. Additional testing would be required to determine if the positive reading was actually the result of TDI exposure. Although the presence of TDI antibodies may indicate exposure to TDI, it does not show when, or how that exposure took place.

The presence of TDI-specific antibodies found in individuals with no known occupational exposures to TDI is a strong indication that significant exposures to TDI are occurring in individuals living near the TAC facility.

  There is no evidence that exposures are occurring now. Further, as stated above, a positive indication of TDI antibodies does not necessarily indicate any exposure to TDI.

To date, one resident has tested positive for both the TDI antibodies (IgG and IgE); three separate evaluations of the resident's blood serum have confirmed the results.

In addition, one of the two ATSDR employees who reported TDI-like health effects while in the community has tested positive and has been confirmed for one of the two TDI antibodies.

To further characterize the residential exposure to TDI and other isocyanates, ATSDR is working to augment Duke University medical evaluations by gathering additional biological samples to be

  According to the laboratory that performed the evaluations, this is not correct.

analyzed for antibodies to isocyanates (TDI, HDI, and Diphenylmethylene Diisocyanate [MDI]). ATSDR worked with the Randolph County Health Department to conduct this exposure investigation September 21 - 22; 112 blood samples were collected.

Public Health Implications

  HDI is not used in the manufacture of flexible polyurethane foam.

The exact amount of TDI required to cause adverse health effects is unknown. People have become sensitized after being exposed to as little as 20 parts per billion (ppb) [17]. After

  Only a "TDI challenge" test can confirm sensitization to TDI.

sensitization there is no amount of TDI that one may be exposed to safely [18]. Studies have shown that in sensitized individuals, asthmatic attacks can occur after exposure to TDI air concentrations as low as 0.l ppb [20].

Individuals who live near the TAC facility or are otherwise near the TAC facility for significant periods of time have reported a number of adverse health effects, including but not limited to dizziness, breathlessness, headaches, nausea, loss of memory, flushing of the face and neck, fatigue, lethargy, sleeping difficulties, and asthma.

  According to the TDI exposure model prepared by an independent consultant following EPA-approved modeling procedures, TDI exposures are much lower than 0.1 ppb (100 parts per trillion).

These adverse health effects are consistent with effects resulting from inhalation exposure to hazardous substances such as TDI/isocyanates and methylene chloride. These individuals include residents as well as personnel from DENR and ATSDR.

  These ill effects could also be caused by exposure to other compounds. Further investigation is needed.
Analytical data of HDI/TDI in off-site air, along with the health complaints of residents in the community near the foam plant which are consistent with TDI exposure, indicate that the Trinity Foam Plant may pose a serious threat to public health for people in the surrounding community and possibly for workers at the facility.   The finding of HDI raises serious questions about the accuracy of the analysis since HDI is not used in the manufacturing of polyurethane foams.

The OVAs do not indicate which specific organic compound the instrument is detecting and measuring.

  Since the compounds are unknown, further tests should be conducted to identify them.

However, the unknown nature of the organic compound or compounds being measured at levels above 1.0 unit (ppm) by the OVA requires that ATSDR assume they are of potential health and safety concern and thus implement certain employee health and safety policies and procedures.

  If the OVA's analysis at levels above 1 ppm require that ATSDR assume a potential health and safety concern, then the regulation is technically unsound. These levels can be obtained almost anywhere at anytime. Since the compounds are unknown, further tests should be conducted.

Until the specific organic contaminants in the ambient air are identified and characterized, any agency personnel present during elevated OVA readings (1 - 5 ppm) must wear EPA Level C respiratory protection.

Use of EPA Level C respiratory protection requires proper training and medical clearance; agency personnel who are not properly trained and medically cleared are required to leave the area immediately when OVA readings indicate volatile organic compounds at levels of 1 - 5 ppm [21].

This ATSDR policy is consistent with the EPA's guidelines: "A range of background to 5 ppm above ambient background concentrations of vapors/gases in the atmosphere has been established as guidance for selecting Level C protection.

 
If this is the case, we should wear a Level C respirator day and night. Highway workers and gas station attendants would require such protection.

Concentrations in the air of unidentified vapors/gases approaching or exceeding 5 ppm would warrant upgrading respiratory protection to a self-contained breathing apparatus" [22].

Because the OVA readings that exceed 1.0 unit (ppm) were taken near residences, the potential for exposure of community members is also of public health concern. The episodic nature of these "contaminant release" events makes it difficult to characterize the potential for human exposure fully and to implement appropriate protective public health responses consistently.

BASIS FOR THE ADVISORY

ATSDR issues this public health advisory based on the following:

  • Available information regarding the past, current, and potential future air emissions from the TAC facility on Glenola Industrial Drive.
  This is industry practice when working with isocyanates.
  • The frequency and severity of adverse health effects reported by local residents.
  • The consistent relationship between hazardous substances such as TDI and methylene chloride known to be emitted by this facility and the acute and chronic symptoms reported by residents (including difficulty breathing, difficulty concentrating, poor memory, and dull headaches).
  • The confirmed measurement of isocyanates in the ambient air of the community at levels known to produce the reported health effects in sensitized individuals, such as bronchial hyperresponsiveness, and declines in lung function.
  • The presence of biomarkers of exposure to isocyanates in the blood of some individuals who reside or otherwise spend time near the TAC facility and who have reported health effects that are plausibly related to exposure to isocyanates and other hazardous contaminants.

CONCLUSIONS

  The number of local residents who reported adverse health effects was not stated.

Based on the available information, ATSDR concludes that hazardous substances are being emitted from the Trinity American Corp. facility on Glenola Industrial Drive in Randolph County, North Carolina. These emissions are resulting in off-site air concentrations of contaminants at levels that may pose a serious threat to public health.

  This conclusion is not and cannot be supported based on the reported data, flawed science, and debatable biological monitoring results.

RECOMMENDATIONS AND PROPOSED ACTIONS

ATSDR recommends that appropriate agencies take the following actions:

 

PFA would like to obtain details regarding the confirmatory air sampling and analysis that has reportedly confirmed the presence of TDI and purported HDI in the community's air.

  1. Use their statutory, regulatory, or administrative authorities to implement measures that will immediately reduce or eliminate opportunities for residential exposures to hazardous substances emitted from the TAC facility.
  2. Conduct environmental sampling as appropriate (air, private well water, surface water, surface soil, and biota) to facilitate qualitative and quantitative estimates of residential exposures under a variety of scenarios.
  3. Investigate the TAC facility and interview employees to assess occupational exposures.
  4. Provide local health care providers and public health officials with necessary information on the diagnoses and treatment of symptoms and health effects associated with environmental exposures to the specific chemicals and classes of chemicals identified.
  5. Conduct biomedical testing (analyses of blood) for biomarkers of exposure to TDI and other isocyanates among community members and TAC employees.
  6. Consider studies (including biomarkers of effect) for the prevalence of various exposure-related health effects among residents and TAC employees.

For additional information, please contact ATSDR at the following address:

Robert C. Williams, P.E., DEE
Director, Division of Health Assessment and Consultation
Agency for Toxic Substances and Disease Registry
1600 Clifton Road NE (E32)
Atlanta, Georgia 30333
(404) 639-0610

REFERENCES

  1. Results of Agency for Toxic Substances and Disease Registry/North Carolina Department of Environment, Health and Natural Resources TDI monitoring from May 19, 1997, through June 1, 1997.
  2. Roy F. Weston.. Memorandum to Beth Mileson, North Carolina Department of Environment, Health and Natural Resources, concerning ambient air sampling results (September 19 - 25, 1996). October 9, 1996.
  3. North Carolina Department of Environment, Health and Natural Resources. Analytical results from Air Toxics Analytical Support Team.
  4. Agency for Toxic Substances and Disease Registry. Draft air consultation released for 30-day public comment period. August 27, 1997.
  5. Roy F. Weston. Memorandum to Lori Cherry, North Carolina Department of Environment, Health and Natural Resources concerning DEECO off-gas study. March 17, 1997.
  6. State of North Carolina, County of Randolph. Trinity American Corporation/special order by consent. July 26, 1996.
  7. North Carolina Department of Environment, Health and Natural Resources, Air Quality Toxics Protection Unit. Air Toxics Analytical Support Team (ATAST) report of investigation, Trinity Foam Company, Glenola, NC, Randolph County, investigation #95005, March 14 - September 15, 1996.
  8. US Census Bureau, TIGER/Line Files, 1990 (Archdale, North Carolina), prepared by the Bureau of Census, US Census Bureau, Washington, DC, 1991.
  9. Agency for Toxic Substances and Disease Registry public availability session, Archdale, North Carolina. May 9, 1997.
  10. Agency for Toxic Substances and Disease Registry. Personal communication between Theresa Kilgus and staff of the State of North Carolina Department of Environment, Health and Natural Resources, Air Toxics Analytical Support Team. July 1997.
  11. Agency for Toxic Substances and Disease Registry. Employees incident report concerning exposures to unknown air contaminants identified by OVA readings in exceedance of 5 ppm indicating implementation of Level C personal protective equipment. August 15, 1997.
  12. Levine R, State of North Carolina Department of Environment, Health and Natural Resources. Order of abatement to Trinity American Corp. September 3, 1997.
  13. Zellweger Analytics, Inc. Technical notes on the response verification procedures for chemcassette-based toxic gas monitoring systems. June 3, 1997.
  14. Lesage J, et al. Workers exposure to isocyanates. American Industrial Hygiene Association Journal 1992 Feb; 53:146-53.
  15. Omega Specialty IsoCheck. Marketing information on isocyanate sampling cassette for 2,4 TDI, 2,6 TDI, 1,6 HDI, and MDI. Chelsford, (MA): 1996.
  16. Levine, S.P. et al., "Critical Review of Methods of Sampling, Analysis, and Monitoring for TDI and MDI", American Industrial Hygiene Association Journal 1995 June; 53:146-53.
  17. Unanue ER, Benacerraf B. Textbook of immunology. 2nd ed. Baltimore: Williams and Wilkins, 1984:4.
  18. National Institute for Occupational Safety and Health. Preventing asthma and death from diisocyanate exposure, alert 1996. Department of Health and Human Services; 1996.Publication No.: 96-111, pages 1 - 16.
  19. American Conference of Governmental Industrial Hygienists, Inc. Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati 1991.
  20. Agency for Toxic Substances and Disease Registry. Medical management guidelines for acute chemical exposures (MMGs), toluene diisocyanate. October 1993:1 - 4.
  21. Agency for Toxic Substances and Disease Registry. Health and safety program for hazardous substance field activities: policy and procedures. 1995.
  22. Environmental Protection Agency Office of Emergency and Remedial Response. Standard operating safety guides, PB92-963414. June 1992
  PFA is concerned about the welfare of the people who reported adverse health effects. The findings of the ATSDR do not support its conclusion that TAC's foam operation or the chemicals used in its operation were the proximate cause. The true cause remains unidentified. PFA recommends further study of the site conditions at the time of the complaints to be conducted by independent experts experienced in airborne release modeling. Additional medical and biological studies are also needed under the supervision of specialists experienced with the exposure effects of the chemicals used at the TAC foam facility.