Arthur M. Kaplan

One hundred laboratory-synthesized polyurethanes were tested by a mixed-culture petri dish method for susceptibility to fungus attack. Polyether polyurethanes were moderately to highly resistant to fungal attack, whereas all polyester polyurethanes tested were highly susceptible. The susceptibility of the polyethers was related to the number of adjacent methylene groups in the polymer chain. At least two such groups were required for appreciable attack to occur. The presence of side chains on the diol moiety of the polyurethane reduced susceptibility.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXT2,4,6-Trinitrotoluene-surfactant complexes: decomposition, mutagenicity and soil leaching studiesDavid L. Kaplan and Arthur M. KaplanCite this: Environ. Sci. Technol. 1982, 16, 9, 566–571Publication Date (Print):September 1, 1982Publication History Published online1 May 2002Published inissue 1 September 1982https://pubs.acs.org/doi/10.1021/es00103a006https://doi.org/10.1021/es00103a006research-articleACS PublicationsRequest reuse permissionsArticle Views155Altmetric-Citations48LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Abstract Representative polyolefin films were exposed to UV radiation from light sources having different intensities and spectral distribution including the quartz mercury arc fluorescent lamps, xenon arc, and sunlight. Films exposed were polyethylene, polypropylene, and sensitized polyethylene. The oligomer fractions supported microbial growth, but the high polymers gave minimal or no growth. It was concluded that photooxidative degradation of polyolefins does not per se induce progressive attack by microorganisms. Oligomers present originally in the polymer are augmented by those produced by photooxidation. These oligomers support growth if separated from the polymer matrix. These observations explain some of the contradictory reports in the literature concerning the microbial degradation of sensitized polyolefins.

N-Nitrosodimethylamine (NDMA) was mineralized by microorganisms in aqueous and soil systems. Initial rates of mineralization (micrograms per milliliter per day) were calculated for a wide range of initial concentrations of NDMA (micrograms per milliliter to picograms per milliliter). Log-log plots of the data were fitted with both linear and nonlinear least-squares analyses; however, linear models provided better fits for the kinetic data in all cases. The slopes of the linear fits were not significantly different than 1.0 (P < 0.05); thus, first-order reaction kinetics were in effect over the range of concentrations tested, and saturation kinetics were not achieved. Rate constants (day) and total percent mineralized increased with decreasing initial concentrations of NDMA. Rates of mineralization were reduced in aqueous systems when supplemental carbon was available, whereas in soils, percentages of organic matter and supplemental carbon had little effect on rates of mineralization. Implications of these results for predictions of rates and threshold limits of mineralization activity in natural systems are discussed. A laboratory scale simulated trickling filter containing an activated charcoal bed provided a suitable environment for mineralization of NDMA at concentrations of 50 and 100 mug/ml on a continuous basis. NDMA was not toxic to natural populations of microorganisms at concentrations up to 10 mg/ml. Using high-pressure liquid chromatography coupled with radioactivity detection, we identified formaldehyde and methylamine as intermediates produced during the biodegradation of NDMA.