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M Karstadt

Publications and source records attributed to M Karstadt.

10 recordsLinked to original sources
PubMed1988

Quantitative risk assessment: qualms and questions.

Within the past ten years, quantitative risk assessment has come to play a central role in the federal regulation of carcinogens. Federal agencies use quantitative risk both to set priorities and to establish exposure levels. The use of quantitative risk assessment is mandated by Executive Orders requiring performance of cost-benefit analysis, although performance of assessments has often been ascribed to the Supreme Court decision in the 1980 "benzene" case. Quantitative risk assessment is a deeply flawed methodology with results that give a false sense of certainty and objectivity. Also, the nature of quantitative risk assessment methodologies currently in use makes it difficult for members of the public to scrutinize and assess regulatory actions. Quantitative risk assessment should not be used for regulation of carcinogens, especially not for establishing exposure levels. Instead, alternative methodologies should be utilized, which are appropriately reflective of uncertainty and which are more readily accessible to public scrutiny and participation.

Carcinogens↗
PubMed1984

Access to data on chemical composition of products used in auto repair and body shops.

Some information on chemical composition of products used in the workplace can be obtained by requesting composition data from product marketers. Workers in auto repair and body shops identified 253 products used in their shops. Full disclosure of composition was obtained for approximately 20% of the 174 products marketed by companies which answered our letters. Composition was partially disclosed for approximately 40% of the products, and about 10% of the product formulations were claimed to be trade secret or confidential. The study reported in this paper was carried out in New York State in 1980, before the effective date of the New York State right-to-know law. The results of this study can be used as a benchmark to judge the effectiveness of worker right-to-know laws and product labeling regulations.

Air Pollutants, Occupational↗
PubMed1982

Availability of epidemiologic data on humans exposed to animal carcinogens. II. Chemical uses and production volume.

We report further findings of a survey of manufacturers, processors, and importers of chemicals determined by the International Agency for Research on Cancer (IARC) to be animal carcinogens, but whose carcinogenicity in humans was considered uncertain because of inadequate epidemiologic data. We requested epidemiologic studies from the companies marketing or using any of the 75 IARC animal carcinogens in commerce in the United States. Eighteen of the 75 IARC animal carcinogens had volumes listed of 10(6) lb/year or greater, with 8 of the 13 chemicals for which studies had been completed or are in progress in this "high volume" category. The use category with the largest number of chemicals was drugs--19 of the 75 IARC animal carcinogens were in this category. However, none of the 13 chemicals included in epidemiologic studies was a drug. Seven of the 13 chemicals included in studies were used primarily as pesticides. We received little information on dyes and dye intermediates, experimental carcinogens, and drugs, all of which are produced in relatively low volumes; these categories represent 42 of the 75 IARC animal carcinogens. Low volumes and declining usage/production appear to be barriers to performance of epidemiologic studies. Information we received suggests that sometimes the problem of low production volume may be avoided by studying users rather than production workers. Overall, however, we expect few additional epidemiologic studies of the 75 IARC animal carcinogens.

Animals↗
PubMed1976

PVC: health implications and production trends.

Poly(vinyl chloride) (PVC) is a complex plastic system. Individual components of the PVC system, including residual vinyl chloride monomer (RVCM) and certain additives, may pose risks of harm to human health. There have been significant reductions in the RVCM content of PVC resin since 1974, reducing the cancer risk of workers in PVC fabrication plants and consumers of PVC products. A "no-effect" level for vinyl chloride monomer (VCM)-induced carcinogenesis has not been found to date; therefore, the significance of human exposure to low levels of RVCM remains to be determined. Exposure to PVC dust may cause pulmonary dysfunctions. Pulmonary and other possible health effects of PVC dust require further study. The PVC plastics system should be characterized as to interactions among its various components and as to interactions of the components and the PVC system as a whole with biological systems.

Air Pollutants, Occupational↗
PubMed1969

Azotobacter vinelandii RNA polymerase. VII. Enzyme transitions during unprimed r[I-C] synthesis.

Transitions in the state of RNA polymerase were demonstrated during the unprimed synthesis of the r[I-C] copolymer. No detectable change in the usual dimer-monomer pattern was noted during the lag phase (0-25 min at 37 degrees ) after analysis of the reaction mixture by acrylamide gel electrophoresis. At the end of the lag phase, a major alteration in the electrophoretic pattern occurred, marked by the disappearance of the dimer-monomer bands and the concomitant appearance of a series of monomer-r[I-C] copolymer complexes. As these complexes of r[I-C] copolymer with one or more polymerase monomer were formed, an enzymatically inactive component (gamma protein) of the polymerase was displaced. During the phase of rapid r[I-C] copolymer synthesis, the active form of the A. vinelandii RNA polymerase was the r[I-C] monomer lacking the gamma protein.

Azotobacter↗