Butyltins in sediments from Boston Harbor, USA

Sediments from 12 sites in Boston Harbor were assayed for butyltins. The highest levels of tributyltin (TBT) were found at sites where commercial or pleasure boats were moored, where ocean going vessels dock, and at a former shipyard. Little or no TBT was detected at sites which do not have a history of significant boating activity. Dibutyltin and monobutyltin were also detected at most sites, indicating that degradation of TBT occurs at these sites.     

Simulation of effects of atmospheric ethylene on tree leaf shedding

This study made a preliminary assessment of the possibility that ethylene contained in polluted atmospheres affects leaf shedding of trees. The effect of ethylene dosage (ppb x h) on leaf shedding at various temperatures was approximated by using a polynomial regression. The effect of ethylene dosage on shedding of tree leaves with various sensitivities to this hydrocarbon was simulated in connection with the relationship between ethylene concentrations (10-100 ppb), dosage periods (0-50 days) and temperature (10-30 degrees C). The simulated results indicated the possibility that, for the tree group having high sensitivity, the rate of leaf shedding due to a dosage of ethylene with a concentration as low as 20 ppb, which is commonly observed in urban atmospheres, increased with temperature. On the other hand, the same concentration scarcely influenced leaf shedding in the low sensitivity group even at a temperature as high as 30 degrees C. The results for the real atmosphere determined at the Tokyo metropolitan center indicated the possibility that, for trees having high sensitivity, the rate of leaf shedding increased with rises in both monthly ethylene concentrations and air temperatures and reached a maximum of 90% in July. But in December when the concentration again reached the same value as in July while the mean monthly air temperature was 9.3 degrees C, the rate was only 10%.     

Primary biodegradation of linear alkyltoluene and alkylbenzene sulfonates

Studies on the primary biodegradation of linear dodecylbenzene sulfonate, linear dodecyltoluene sulfonate, linear C(10-14) benzene sulfonate, linear C(10-14) toluene sulfonate, commercial samples of linear C(10-14) benzene sulfonate and branched dodecylbenzene sulfonate (DDBS) were carried out using a microbial culture developed from garden soil. Results show that linear alkyl toluene (LAT) is as degradable as linear alkylbenzene (LAB) in 7 days. However, a slower rate of degradation was noted with LAT. Various distributions of the positional isomers of the phenyl ring in the alkane chain of C(10-14) LAB showed no change in the pattern of primary biodegradation.     

Perspectives of a large scale environmental survey for chlorinated dioiins: water analyses

During 1983 and 1984, The Dow Chemical Company conducted a study to determine the extent of dioxin contamination at its Midland, Michigan plant and the surrounding area. The primary objectives of this study were to identify, rank order, and when possible quantify potential sources of dioxins to the environment and also to determine the extent of contamination in areas affected by the Dow facility. Early in the study, it was estimated that approximately 0.6g/year of 2378-TCDD was being emitted in 2.5 × 10¹⁰L of wastewater effluent. Data will describe observed sources of TCDD (both current and historical), environmental levels, existing water treatment methods, control measures taken, and future improvements on the water system to reduce TCDD in the effluent.     

Elimination of 2-halogenobenzanilides

The elimination of 2-halogenobenzanilides has been studied in the rat, over 75% of the oral dose being excreted in 3 days. The higher the molecular weight of the compound, the more important was the faecal elimination route. No such association was seen for biliary secretion.     

Detection of polycyclic aromatic hydrocarbons in skin oil obtained from roofing workers

Twelve polycyclic aromatic hydrocarbons have been analyzed in blood serum and skin oil collected from roofing workers. Although a range of 0.05–36 ng was observed in skin oil samples, none was detected in serum, at detection limits of 1–175 pg/ml.     

Isolation and identification of arsenobetaine from the American lobster Homarus amerjcanus

The naturally occurring arsenic compound present in the muscle tissue of the American lobster, Homarus americanus has been isolated and shown to be arsenobetaine.     

Distribution of organotin compounds in tissues of mussels Mytilus edulis and clams Mya arenaria

Concentrations and composition of butyltin (BT) and phenyltin (PT) compounds were compared in tissues of mussels Mytilus edulis and clams Mya arenaria collected from the Mersey Estuary. Tributyltin (TBT) concentrations were consistently highest in digestive gland and low in muscular tissues such as siphons (Mya) and adductor muscle (Mytilus). Lowest concentrations were found in the periostracum surrounding the siphons of Mya. Ratios of monobutyltin (MBT), dibutyltin (DBT) and TBT to total BT content of Mytilus tissues were in the ranges 25-34%, 21-28% and 44-51%, respectively. Much higher proportions of TBT:total BT were characteristic of Mya (>80% in the digestive gland, remaining tissue and gonad) implying that slow degradation rates account for the relatively high levels of TBT in this species. TPT was the only phenyltin compound detected (albeit at relatively low levels), and, like TBT, was present in highest concentrations in the digestive gland of clams--suggesting an important dietary component in the accumulation of OTs in these bivalves.