Functional rectal carcinoid tumour and ocular myopathy

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Degradation of polychlorinated biphenyls by two species of Achromobacter

Two species of Achromobacter were isolated from sewage effluent using biphenyl (BP) and p-chlorobiphenyl (pCB) respectively as sole carbon sources. Achromobacter BP grown on biphenyl accumulated a product with an ultraviolet absorption maximum at 257 nm which could not be identified. Washed cell suspensions of both isolates oxidized biphenyl, o-phenylphenol, phenylpyruvate, catechol, p-chlorobiphenyl, m-chlorobiphenyl, o-chlorobiphenyl, o,o′-dichlorobiphenyl, and p,p′-dichlorobiphenyl. Both isolates produced meta cleavage products by fission of the benzene ring. However, spectral characteristics of degradation products from respective substrates were different between the two isolates, indicating divergent degradation pathways. Benzoic and p-chlorobenzoic acids were produced from the degradation of BP and pCB, respectively, by Achromobacter pCB. Chloride was not produced by either isolate during the degradation of all chlorobiphenyls tested including the growth of Achromobacter pCB on p-chlorobiphenyl.

CYTOLOGICAL EFFECTS OF THE PESTICIDES PHOSDRIN AND BLADEX ON TRADESCANTIA AND VICIA FABA

The cytological effects of the insecticide Phosdrin (mevinphos) and the herbicide Bladex on root tips of Tradescantia and Vicia faba were observed and compared with those of the chemical mutagen ethyl methane sulfonate (EMS). In addition, plants of Vicia faba were sprayed prior to floral initiation and pollen mother cells examined for chromosomal abnormalities. Phosdrin and Bladex produced the same kinds of chromosome abnormalities as EMS, namely, fragments, bridges, multipolar anaphases and lagging chromosomes. Bladex produced a higher percentage (3.47%) of chromosome aberrations in root tips of Tradescantia than did Phosdrin (2.56%), but fewer in Vicia faba than did either EMS or Phosdrin. Bladex was more toxic to cells of Vicia faba. The greater percentage of chromosome fragments induced by both pesticides in Vicia faba may be the result of highly specific and localized action of the pesticides in heterochromatic regions. Vicia faba seedlings sprayed with Phosdrin had a greater percentage of chromosome aberrations in the pollen mother cells than were found in root tips after Phosdrin treatment. Bladex sprayed at the same concentration as Phosdrin (200, 400, 600 ppm) was lethal to the plants. The frequency of chromosomal aberrations induced by both pesticides deviated significantly from that of the control.