USEPA

In 1986, David Weininger created the SMILES Simplified Molecular Input Line Entry System) notation at the US Environmental Research Laboratory, USEPA, Duluth, MN, for chemical data processing. The chemical structure information is highly compressed and simplified in this notation. The flexible, easy to learn language describes chemical structures as a line notation [20, 21]. The SMILES language has found widespread distribution as a universal chemical nomenclature... 

G. S. Sayler, Microbial Decomposition of Chlorinated Aromatic Compounds, USEPA 600/2-86/090, Washington, D.C., 1986. 

R. F. Carsel and co-workers. Users Manual for the Pesticide Toot Zone Model (PRZM), Release I, USEPA 600/3-84-109, Washiagton, D.C., 1984. 

Sodium chlorite is not Hsted by the USEPA or any regulatory authority as a carcinogen. Studies conducted ia mice and rats did not show an increase in tumors in animals exposed to sodium chlorite in thek drinking water. Sodium chlorite has been found to have mutagenic activity in some in vitro test systems such as the Ames Salmonella reverse mutation assay without the presence of metaboHc activators. The significance of these test results in regard to human health is not clear because of the oxidizing effects of the chlorite ion (149). 

More than 80% of all the sodium chlorite produced is used for the generation of chlorine dioxide. Sodium chlorite or the chlorine dioxide generated from it or from sodium chlorate must be registered with the USEPA for each specific appHcation use as a biocide for microbial growth control or disinfection. These regulations are covered under the Eederal Insecticide, Eungicide, and Rodenticide Act (EIERA). 

Until recently, few papers appeared on the fate of dyes in the environment. But because of the importance of this subject, work is being done primarily by the U.S. Environmental Protection Agency (USEPA) and the Ecological and Toxicological Association of the Dyestuff Manufacturing Industry (ETAD). 

The Toxic Substances Control Act (TSCA) was enacted in 1976 to identify and control toxic chemical ha2ards to human health and the environment. One of the main provisions of TSCA was to estabUsh and maintain an inventory of all chemicals in commerce in the United States for the purpose of regulating any of the chemicals that might pose an unreasonable risk to human health or the environment. An initial inventory of chemicals was estabhshed by requiring companies to report to the United States Environmental Protection Agency (USEPA) all substances that were imported, manufactured, processed, distributed, or disposed of in the United States. Over 50,000 chemical substances were reported. PoUowing this initial inventory, introduction of all new chemical substances requires a Premanufacturing Notification (PMN) process. To be included in the PMN are the identity of the new chemical, the estimated first year and maximum production volume, manufacture and process information, a description of proposed use, potential release to the environment, possible human exposure to the new substance, and any health or environmental test data available at the time of submission. In the 10 years that TSCA has been in effect, the USEPA has received over 10,000 PMNs and up to 10% of the submissions each year are for dyes (382)... 

The large number of dyes and the potential for toxicity of dyes and dye components have made this class of compounds one of the most extensively reviewed and regulated. Up until 1987, 765 PMNs for dyes have been submitted by 53 different companies and over 50% of these notices by six companies. Figure 2 shows PMN dyes received by the USEPA, described by principal color forming group (382). 

G. M. Shaul, C. R. Dempsey, and K. A. Dostol, Fate of Water Soluble A p Djes in the Activated S ludge Process, EPA/600/2-88/030, report of the Water Engineering Research Laboratory, Office of Research and Development, USEPA, Cincinnati, Ohio, July, 1988. 

T. M. Keinath, Technology Evaluation for Priority Pollutant Removalfrom Dyestuff Manufacture Wastewaters, USEPA report 600/S2-84-055, Washington, D.C., Apr. 1984. 

Pollution Prevention Mews, Office of Pollution Prevention, USEPA, Washington, D.C., Api. 1990, p. 2 Pollution Prevention Guidance Manualfor the Dye Manufacturingindustry, USEPA/ETAD, Washington, D.C., 1992. 

Tabak, et al., Biodegradability Studies with Organic Priority Pollutant Compounds," USEPA, MERL, Cincinnati, Ohio, April 1980. 

As discussed in the introduction, the hierarchy set forth by the USEPA in the Pollution Prevention Act establishes an order to which waste-management activities should be employed to reduce the quantity of waste generated. The preferred method is source reduction, as indicated in Fig. 25-1. This approach actually precedes traditional waste management by addressing the source of the problem prior to its occurrence. 

Detecting Leaks Small leaks are difficult to detect. The USEPA and American Petroleum Institute standard for nonlealdng underground tanks is 0.05 gaUh (3.15 cmVmin), above which a tank is considered to be leaking. Leak detection measurements can be influenced by many factors, making it difficult to detect small leaks. 

Large Fans These could be used to dilute a vapor cloud below its LFL with ambient air (see, for example, Whiting and Shaffer, Feasi-bihty Study of Hazardous Vapor Amelioration Techniques, Proc. 1978 Nat. Conf. on Control of Hazardous Material Spills, USEPA, Miami Beach, April 1978). But caution must be exercised because the turbulence produced by fans will likely promote rapid combustion and a resulting UVCE unless vapors are diluted below the LFL. Nevertheless, in new plants, strategic placement of air coolers may provide enough air flow to reduce the risk of a UVCE. 

United States Environmental Protection Agency, Toxics in the Community National and Local Perspectives, USEPA, USA, 1991. 

The particles most likely to cause adverse health effects are the fine particulates, in particular, particles smaller than 10 p and 2.5 mm in aerodynamic diameter, respectively. They are sampled using (a) a high-volume sampler with a size-selective inlet using a quartz filter or (b) a dichotomous sampler that operates at a slower flow rate, separating on a Teflon filter particles smaller than 2.5 mm and sizes between 2.5 mm and 10 mm. No generally accepted conversion method exists between TSP and PM,o, which may constitute between 40% and 70% of TSP. In 1987, the USEPA switched its air quality standards from TSP to PMk,. PM,q standards have also been adopted in, for example, Brazil, Japan, and the Philippines. In light of the emerging evidence on the health impacts of fine particulates, the USEPA has proposed that U.S. ambient standards for airborne particulates be defined in terms of fine particulate matter. 

The most frequently used reference guidelines for ambient particulate concentration are those of WHO, the EU, and the USEPA. These guidelines are based on clinical, toxicological, and epidemiologic evidence and were established by determining the concentrations with the lowest observed adverse effect (implicitly accepting the notion that a lower threshold exists under which no adverse human... 

USEPA (U.S. Environmental Protection Agency). 1988. Pesticide Waste Control Technology. Park Ridge, N.J. Noyes Data Corporation. 

USEPA (United States Environmental Protection Agency). 1982. Development Document for Effluent Limitations Guidelines and Standards for the Iron and Steel Manufacturing Point Source Subcategory. EPA440/ 1-82/024. Washington, D.C. 

Cleaner Technologies Substitute Assessments A Methodology and Resource Guide, USEPA, EPA Document Number EPA 744-R-95-002, December 1996. 

Chapter 5 describes simplified methods of estimating airborne pollutant concentration distributions associated with stationary emission sources. There are sophisticated models available to predict and to assist in evaluating the impact of pollutants on the environment and to sensitive receptors such as populated areas. In this chapter we will explore the basic principles behind dispersion models and then apply a simplified model that has been developed by EPA to analyzing air dispersion problems. There are practice and study problems at the end of this chapter. A screening model for air dispersion impact assessments called SCREEN, developed by USEPA is highlighted in this chapter, and the reader is provided with details on how to download the software and apply it. 

Pesticides Toxics Branch USEPA Region 1 (APT2311)... 

Toxics Pesticides Branch USEPA Region 3 (3HW42)... 

Pesticides Toxic Substances Branch USEPA Region 5 (5SPT-7)... 

Office of Congressional and Intergovernmental Liaison USEPA Region 7 (CIGL)... 

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