The once and future threat of the petrochemical industry to the world of life.

In the last 50 years, the petrochemical industry has massively introduced thousands of synthetic organic chemicals into the environment, only recently acknowledging that most of them are hazardous to living things. The industry has unwittingly appropriated from the living world its once-exclusive capability to produce organic chemicals, but has created substances, such as DDT, dioxin, and PCBs, that do not occur in living things and are therefore untested by the long course of evolution. Now, transmuted into biotechnology, the industry is making the same mistake.

Modeling the atmospheric transport and deposition of PCDD/F to the Great Lakes.

Atmospheric deposition is a significant loading pathway for polychlorinated dibenzo-p-dioxins and dibenzofurans (dioxin) to the Great Lakes. An innovative approach using NOAA's HYSPLIT atmospheric fate and transport model was developed to estimate the 1996 dioxin contribution to each lake from each of 5,700 point sources and 42,600 area sources in a U.S.

Population, development, and the environment: trends and key issues in the developed countries.

The quantitative relationship between environmental degradation (pollution) and the factors that influence it can be expressed by the identity: Pollution = population x (good/population) x (pollution/good), where "affluence" is expressed as good/population and the technology of production as pollution/good. Annual data for the emission of carbon monoxide and nitrogen oxides from mobile sources and for the use of pesticides and inorganic nitrogen fertilizer from agriculture, for the member countries of the Organization for Economic Cooperation and Development and the United States, were analyzed to determine the relative change in the three factors over the period 1970-1987. In each case the considerable variation in pollutant emissions among the different countries is most closely related to the concomitant change in the technology factor (pollution/good).

Rapid population growth and environmental stress.

It is often suggested that rapid population growth, especially in developing countries, correspondingly intensifies environmental degradation, which must therefore be mitigated by reducing the rate of population growth. The validity of this assumption can be tested by means of an algebraic identity that relates the amount of a pollutant introduced into the environment to the product of three factors: population, "affluence" (the amount of goods produced per capita), and "technology" (the ratio of pollution generated to goods produced). For several forms of pollution that have a known origin in a specific production process (electricity production, use of motor vehicles, and consumption of inorganic nitrogen fertilizer), it is possible to compare the inferred rate of increase in pollution levels with the rate of population growth in developing countries.

The mutagenicity of cigarette smokers' urine.

Using the methods of Yamasaki and Ames (1977), we have studied the mutagenicity of urine samples from 29 cigarette smokers and 14 nonsmokers. Duplicate plates at each dose yield reproducible dose-response curves, evening and 24-hour samples of smokers' urine have similar levels of mutagenic activity, as do evening samples from the same smoker from different days. Smokers' daily cigarette tar intake is correlated with urinary mutagen concentration, but the correlation achieves statistical significance only in the sub-sample of smokers over 25 years old.

Mutagenic Analysis as a Means of Detecting Carcinogens in Foods .

The Ames test is a valuable screening procedure for environmental carcinogens which are believed to be responsible for a large part of the cancer incidence in the U.S. Mutagens originally detected in bacterial nutrient containing "beef extract" have now been detected in commercial beef extract and in commercial foods containing beef extract.

Formation of mutagens in beef and beef extract during cooking.

Mutagens, distinguishable from benzo[a]pyrene and from mutagenic amino acid and protein pyrolysis products, are formed when ground beef is cooked in a home hamburger cooking appliance or when beef stock is concentrated, by boiling, to a paste known commercially as beef extract. "Well-done" hamburgers contain about 0.14 part per million of the mutagens, and beef bouillon cubes which contain beef extract about 0.

Environmental mutagens in urban air particulates.

A bioassay capable of detecting carcinogenic substances that are associated with the elevated incidence of cancer in the urban environment would be important for epidemiologic and environmental analyses. The feasibility of using the Salmonella mutagenesis system developed by Ames for this purpose has been tested by analyzing Chicago air particulate samples. Active material, as evidenced by enhanced rates of mutation, both in the presence of microsomes and in their absence, is readily extractable from samples of air particulates.

Isolation of mutagens from bacterial nutrients containing beef extract.

The enhanced rate of mutation of Salmonella strain TA1538 (Ames) by microsomes results from the presence of about 2--5 ppm of microsome-activatable mutagens in bacterial nutrient broths that contain beef extract. Since mutagens toward Salmonella are likely to be carcinogenic, the data have significant implications for the problem of carcinogenesis.