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easier to control chemicals under their standard than under the unreasonable risk 

 standard in TSCA. 



In Germany, the major focus of the chemical control law is to classify and label 

 chemical products on the basis of their toxicity. In addition to determining the label- 

 ing of a chemical, classification is the starting point for risk assessment. The classi- 

 fications also drive downstream legislation concerned with aspects of risk manage- 

 ment, such as worker protection. The risk assessments can-result in additional test- 

 ing or the imposition of certain controls on the chemical, such as use restrictions. 

 Bans or major restrictions on chemicals are rare, especially for existing chemicals, 

 because of the complex process established for taking these actions. 



In Sweden, the major focus is also on classification and labeling of chemicals on 

 the basis of their toxicity. Certain mandatory controls are established for each clas- 

 sification category. Use restrictions may also apply, depending on the chemical's 

 classification. Although the Swedish government has banned or severely restricted 

 only a few chemicals, it has established a list of 13 undesirable chemicals, such as 

 lead and mercury, that it wants to eliminate or significantly reduce by the year 

 2000. 



CHEMICAL REVIEW UNDER TSCA 



In requiring EPA to review new chemicals, TSCA recognizes that the best time 

 to assess the risks of chemicals is before they enter commerce and can cause harm. 

 EPA's authority to review the risks of existing chemicals is also important for two 

 reasons. First, about 62,000, or 86 percent, of the approximately 72,000 chemicals 

 in the TSCA inventory were in commerce when the new chemical review program 

 began in 1979 and have not been reviewed as new chemicals. Second, the risks of 

 a new chemical can change once it enters commerce and becomes an existing chemi- 

 cal. More may be learned about its toxicity, or exposures to the chemical can change 

 as the amounts produced or how the chemical is used changes. 



REVIEW OF NEW CHEMICALS 



TSCA does not require routine chemical testing, and the chemical industry per- 

 forms limited testing on new chemicals. In a 1990 study, EPA found that 51 percent 

 of premanufacture notices did not include any test data on toxicity, physical chemi- 

 cal properties, and environmental fate. The data that were provided frequently con- 

 sisted of studies on short-term health effects. 



Because sufficient test data are generally not available for new chemicals, EPA 

 uses a method known as structure activity relationships analysis to predict chemi- 

 cals' health and environmental effects. This method relies on test data from chemi- 

 cals with similar molecular structures. In 1993, EPA completed a study in which 

 the agency's predictions using this method were compared with actual test results 

 for new chemicals in the European Community. Although EPA's predictions were 

 highly accurate for some characteristics, they were often inaccurate for many others. 

 For example, the predictions on biodegradation agreed with the test data for 93 per- 

 cent of the chemicals. However, EPA had only a 63-percent accuracy rate in predict- 

 ing vapor pressure, an important factor in determining the amount of potential ex- 

 posure to a chemical. Both EPA and European Community officials considered this 

 accuracy rate too low to adequately characterize chemical risks. 



Another uncertainty limits EPA's assessments of risks posed by new chemicals. 

 EPA uses the manufacturers' or processors' estimates of anticipated production vol- 

 umes and uses of the chemicals to estimate potential exposure. However, actual pro- 

 duction volume and chemical uses can change substantially once EPA's assessment 

 is completed and the chemical enters commerce. 



In Canada and Germany, the government also reviews new chemicals before they 

 enter commerce. However, unlike the U.S. practice, these countries require manu- 

 facturers to test the chemicals and submit the results, along with exposure-related 

 information, to the government at the beginning of the review process. Manufactur- 

 ers conduct additional testing as the volume of production increases. On the other 

 hand, Sweden's Act on Chemical Products places the main responsibility on chemi- 

 cal manufacturers and importers to assess the risks of both new and existing chemi- 



