Abstract  As a part of EPA’s comprehensive approach to enhance the Agency’s management of existing chemicals, in March 2012 EPA/OPPT identified a work plan of chemicals for further assessment under the Toxic Substances Control Act (TSCA)2. After gathering input from stakeholders, EPA/OPPT developed criteria used for identifying chemicals for further assessment3. The criteria focused on chemicals that meet one or more of the following factors: (1) potentially of concern to children’s health (for example, because of reproductive or developmental effects); (2) neurotoxic effects; (3) persistent, bioaccumulative and toxic (PBT); (3) probable or known carcinogens; (4) used in children’s products; or (5) detected in biomonitoring programs. Using this methodology, EPA/OPPT identified a TSCA Work Plan of chemicals as candidates for risk assessment in the next several years. In the prioritization process, 1,4-dioxane was identified for assessment based on classification as a probable human carcinogen, wide use in consumer products, high reported releases to the environment, and presence in groundwater, ambient air and indoor environments. EPA/OPPT is performing risk assessments on chemicals in the work plan. If an assessment identifies unacceptable risks to humans or the environment, EPA will pursue risk management. The target audience for the final risk assessment is primarily EPA risk managers; however, it may also be of interest to the broader risk assessment community as well as US stakeholders interested in 1,4-dioxane. The information presented in the risk assessment may be of assistance to other federal, state and local agencies as well as to members of the general public who are interested in understanding whether there are risks from exposure to 1,4-dioxane. The initial step in the EPA/OPPT risk assessment development process, which is distinct from the initial prioritization exercise, includes planning, scoping and problem formulation. During these steps EPA/OPPT may review currently available data and information, including but not limited to, assessments conducted by others (e.g., authorities in other countries), published or readily available reports and published scientific literature. The problem formulation data review could result in refinement of pathways of interest previously identified in the initial prioritization. This document includes the results of scoping, problem formulation, and initial assessment for 1,4-dioxane. In the scoping stage, EPA/OPPT determined which chemical(s) to include and what uses to consider in the assessment. During problem formulation, EPA/OPPT identified available fate, exposure and hazard data, and characterized potential exposures, receptors and effects. EPA/OPPT developed a conceptual model and an analysis plan as a result of problem formulation.

Abstract  OSHA compliance officers often take industrial hygiene samples when monitoring worker exposures to chemical hazards. Many of these samples are submitted to the Salt Lake Technical Center (SLTC) for analysis. The sampling results included on this web page represent the records of the SLTC sampling information system from 1984 forward. They include data on personal, area, and bulk samples for various airborne contaminants. All inspection sampling results will be included here once the case is closed. OSHA does not publicly disclose information from the following types of cases: open inspections and citations currently under contest or under appeal to the Occupational Safety and Health Review Commission or the U.S. Courts of Appeals. After litigation has concluded, the sampling data from the related inspection will be added at the next scheduled update. OSHA updates the data on this web page semi-annually in January and July. Personal sampling results represent the exposure to the individual who was actually wearing a sampling device. Area samples are taken in a fixed location and results may represent the potential risk from airborne contaminants or physical agents to workers in that area. Bulk samples were taken to verify if certain constituents are present and if so, in what concentration. Bulk samples are used individually or in conjunction with personal or area samples to help interpret the level of worker risk. Please note that these results represent individual samplers that may be changed several times during the work shift. As a result, these values may not be directly comparable to levels listed in OSHA's Permissible Exposure Limits (PEL).

Abstract  1,4-dioxane is a solvent used in laboratories and in adhesive products used in celluloid film processing. It's also found as a by-product in some surfactants and emulsifiers used in consumer products: detergents, cosmetics and pharmaceutical products. The National Industrial Chemical Notification and Assessments Scheme (NICNAS) assessed 1,4-dioxane in May 1994. Following are the main findings of the assessment. A workplace product containing more than 0.1% 1,4-dioxane is classed as a hazardous substance. 1,4-dioxane is in Class 3, (Packing Group II) under the Australian Dangerous Goods Code. 1,4-dioxane is highly flammable and may react with light and air to form explosive substances. It is a scheduled poison with limits set for the levels in consumer products. 1,4-dioxane poisoning can occur through the skin, swallowing or by inhalation. Of these, breathing 1,4-dioxane vapour is the most likely way for poisoning to occur. High exposure can result in liver and kidney damage and death. 1,4-dioxane is an eye and respiratory irritant. 1,4-dioxane causes cancer in animals after prolonged exposure.

Abstract  BACKGROUND: Based on the Estimation and Assessment of Substance Exposure (EASE) predictive model implemented into the European Union System for the Evaluation of Substances (EUSES 2.1.), the exposure to three chosen organic solvents: toluene, ethyl acetate and acetone was estimated and compared with the results of measurements in workplaces.

MATERIAL AND METHODS: Prior to validation, the EASE model was pretested using three exposure scenarios. The scenarios differed in the decision tree of pattern of use. Five substances were chosen for the test: 1,4-dioxane tert-methyl-butyl ether, diethylamine, 1,1,1-trichloroethane and bisphenol A. After testing the EASE model, the next step was the validation by estimating the exposure level and comparing it with the results of measurements in the workplace. We used the results of measurements of toluene, ethyl acetate and acetone concentrations in the work environment of a paint and lacquer factory, a shoe factory and a refinery. Three types of exposure scenarios, adaptable to the description of working conditions were chosen to estimate inhalation exposure.

RESULTS: Comparison of calculated exposure to toluene, ethyl acetate and acetone with measurements in workplaces showed that model predictions are comparable with the measurement results. Only for low concentration ranges, the measured concentrations were higher than those predicted.

CONCLUSIONS: EASE is a clear, consistent system, which can be successfully used as an additional component of inhalation exposure estimation. If the measurement data are available, they should be preferred to values estimated from models. In addition to inhalation exposure estimation, the EASE model makes it possible not only to assess exposure-related risk but also to predict workers' dermal exposure.

Abstract  The carcinogenicity and/or mutagenicity as well as structural features and relationships of the glycidylethers (principally phenyl-, butyl-, allyl-, and isopropyl-), dioxane, nitroalkanes (nitro methane, ethane and propane), dimethylformamide and allyl derivatives (chloride, alcohol and amine) were examined. Additionally, considerations of the production, use patterns, estimated populations at risk, TLV's and metabolism of the above agents were discussed.

Abstract  Increasing regulatory attention to 1,4-dioxane has prompted the United States Air Force (USAF) to evaluate potential environmental liabilities, primarily associated with legacy contamination, at an enterprise scale. Although accurately quantifying environmental liability is operationally difficult given limited historic environmental monitoring data, 1,4-dioxane is a known constituent (i.e., stabilizer) of chlorinated solvents, in particular 1,1,1-trichloroethane (TCA). Evidence regarding the co-occurrence of 1,4-dioxane and trichloroethylene (TCE), however, has been heavily debated. In fact, the prevailing opinion is that 1,4-dioxane was not a constituent of past TCE formulations and, therefore, these two contaminants would not likely co-occur in the same groundwater plume. Because historic handling, storage, and disposal practices of chlorinated solvents have resulted in widespread groundwater contamination at USAF installations, significant potential exists for unidentified1,4-dioxane contamination. Therefore, the objective of this investigation is to determine the extent to which 1,4-dioxane co-occurs with TCE compared to TCA, and if these chemicals are co-contaminants, whether or not there is significant correlation using available monitoring data. To accomplish these objectives, the USAF Environmental Restoration Program Information Management System (ERPIMS) was queried for all relevant records for groundwater monitoring wells (GMWs) with 1,4-dioxane, TCA, and TCE, on which both categorical and quantitative analyses were performed. Overall, ERPIMS contained 5,788 GMWs from 49 installations with records for 1,4-dioxane, TCE, and TCA analytes. 1,4-Dioxane was observed in 17.4% of the GMWs with detections for TCE and/or TCA, which accounted for 93.7% of all 1,4-dioxane detections, verifying that 1,4-dioxane is seldom found independent of chlorinated solvent contamination. Surprisingly, 64.4% of all 1,4-dioxane detections were associated with TCE independently. Given the extensive dataset, these results conclusively demonstrate for the first time that 1,4-dioxane is a relatively common groundwater co-contaminant with TCE. Trend analysis demonstrated a positive log-linear relationship where median 1,4-dioxane levels increased between ∼6% and ∼20% of the increase in TCE levels. In conclusion, this data mining exercise suggests that 1,4-dioxane has a probability of co-occurrence of ∼17% with either TCE and/or TCA. Given the challenges imposed by remediation of 1,4-dioxane and the pending promulgation of a federal regulatory standard, environmental project managers should utilize the information presented in this paper for prioritization of future characterization efforts to respond to the emerging issue. Importantly, site investigations should consider 1,4-dioxane a potential co-contaminant of TCE in groundwater plumes. Integr Environ Assess Manag © 2012 SETAC.

Abstract  BACKGROUND: This paper presents the results of the quantitative study of the airborne chemical substances detected in the conservator's work environment.

MATERIAL AND METHODS: The quantitative tests were carried out in 6 museum easel paintings conservation studios. The air test samples were taken at various stages of restoration works, such as cleaning, doubling, impregnation, varnishing, retouching, just to name a few. The chemical substances in the sampled air were measured by the GC-FID (gas chromatography with flame ionization detector) test method.

RESULTS: The study results demonstrated that concentrations of airborne substances, e.g., toluene, 1,4-dioxane, turpentine and white spirit in the work environment of paintings conservators exceeded the values allowed by hygiene standards. It was found that exposure levels to the same chemical agents, released during similar activities, varied for different paintings conservation studios. It is likely that this discrepancy resulted from the indoor air exchange system for a given studio (e.g. type of ventilation and its efficiency), the size of the object under maintenance, and also from the methodology and protection used by individual employees.

CONCLUSIONS: The levels of organic solvent vapors, present in the workplace air in the course of painting conservation, were found to be well above the occupational exposure limits, thus posing a threat to the worker's health.