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From 1981 to 1987, 26 outbreaks of asthma have occurred in the city of Barcelona, Spain, affecting a total of 687 subjects and causing 1155 emergency room admissions. Assays of urban aerosols collected with high-volume samplers between October 1986 and May 1989 have indicated that soybean dust originating from harbor activities (and not traffic or industrial pollution) is the causal agent for these epidemics. Soybean particulates in the filters have been characterized from the composition of the alcohol fraction, namely, campesterol, stigmasterol, beta-sitosterol, n-triacontan-1-ol, and n-dotriacontan-1-ol, constituting a series of aerosol components correlated with the epidemiologic data. This result has also been confirmed by immunochemical assay of specific soybean allergens. The concentration of these sterols in the air corresponds to a 24-hour average level of soybean dust in the order of 25 micrograms/m3 on epidemic days. These results suggest the advisability of monitoring soybean dust in air particulates of populated areas surrounding soybean storage or processing plants. The techniques presented here afford a simple way for the recognition of soybean dust in aerosols containing high concentrations of organic pollutants of traffic or industrial origin.

The distribution of volatile organic compounds (VOC) in urban-influenced air and river waters was investigated. The aquatic VOC were extracted with the closed-loop stripping technique (CLST) and the airborne compounds were studied using two methods, charcoal and polyurethane foam adsorption. In both types of samples, C1-C5 alkylbenzenes and n-alkanes constitute the two major VOC groups, and the presence of these groups indicates a predominance of petroleum products in these two environmental compartments. Chlorinated compounds such as polychlorobenzenes, polychloronaphthalenes and hexachlorobutadiene are abundant in water samples, whereas tetrachloroethene is the predominant chlorinated airborne VOC. The compounds collected with each sampling system can be described in terms of ranges of volatility. These ranges (expressed as mmHg vapour pressure at 25 degrees C) can be defined approximately as 140 (methylcyclopentane)-0.65 (n-undecane) for charcoal, 5.1 (n-nonane)-0.000061 (n-docosane) for polyurethane foam and 29 (toluene)-0.000029 (n-eicosane) for the CLST. Parallel air sampling with charcoal and polyurethane foam is therefore needed to cover a VOC range similar to that afforded by the CLST in water.

Hydrocarbons and bulk organic matter of two sediment cores (No. 84 and 126, CHAIN 61 cruise) located within the Atlantis II Deep have been analyzed. Although the brines overlying the coring areas were reported to be sterile, microbial inputs and minor terrestrial sources the major sedimentary organic material. This input is derived from the upper water column above the brines. Both steroid and triterpenoid hydrocarbons show that extensive acid-catalyzed reactions are occurring in the sediments. In comparison with other hydrothermal (Guaymas Basin) or intrusive systems (Cape Verde Rise), the Atlantis II Deep exhibits a lower degree of thermal maturation. This is easily deduced from the elemental composition of the kerogens and the absence of polynuclear aromatic hydrocarbons of a pyrolytic origin in the bitumen. The lack of carbon number preference among the n-alkanes suggests, especially in the case of the long chain homologs, that the organic matter of Atlantis II Deep sediments has undergone some degree of catagenesis. However, the yields of hydrocarbons are much lower than those observed in other hydrothermal areas. The effect of lower temperature and poor source-rock characteristics appear to be responsible for the differences.