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Biomedical subjects

I M Davies

Publications and source records attributed to I M Davies.

6 recordsLinked to original sources
PubMed1988

Tributyltin contamination in the Firth of Forth (1975-87).

Contamination of the Firth of Forth (Scotland) by tributyltin compounds leached from antifouling paints has been identified using the degree of penis development (imposex) in the common dogwhelk Nucella lapillus. In 1987, a high degree of imposex was observed in the vicinity of pleasure craft activity, fishing harbours and a boat yard, reflecting localised inputs of tributyltin from these sources. Dogwhelks collected in 1975 from sites comparable to those surveyed in 1987 showed lower degrees of imposex and also a lower incidence of penis development in females.

Animals↗
PubMed1988

The influence of dissolved selenium compounds on the accumulation of inorganic and methylated mercury compounds from solution by the mussel Mytilus edulis and the plaice Pleuronectes platessa.

In laboratory experiments, the effects of dissolved selenate and selenite (2 and 200 micrograms Se l-1) on the accumulation of inorganic and methylated mercury (1 microgram l-1) from solution by mussels (Mytilus edulis) and plaice (Pleuronectes platessa) have been studied. In mussels, selenate, and to a lesser extent selenite, markedly reduced the accumulation of inorganic mercury in gills, mantle, kidney and digestive gland. Selenate at 2 micrograms Se l-1 inhibited methylmercury accumulation in most organs, but the same effect was not observed at 200 micrograms l-1. Selenite had little effect on methylmercury accumulation. In plaice, selenate (2 and 200 micrograms l-1) and selenite (200 micrograms l-1) enhanced the accumulation of inorganic mercury in muscle only, but neither compound had any effect on the accumulation of methylated mercury.

Animals↗
PubMed1987

Recent trends in the incidence of multiple births and associated mortality.

The overall incidence of multiple births in England and Wales, which had been declining since the early 1950s, started to increase in the early 1980s in all age groups except for women under 20. This followed a rise in the incidence of triplet and higher order multiple births which had started in the late 1970s. Analyses of data for births between 1978 and 1983 showed that while stillbirth, perinatal, neonatal, and post-neonatal mortalities among multiple births fell considerably, they remained consistently higher than those for singleton births. Differences in the distribution of birth weight do not wholly explain these differences. Analyses of certified causes of stillbirth and death are difficult to interpret because a considerable proportion were attributed to 'multiple pregnancy'.

Age Factors↗
PubMed1986

Cadmium in edible crabs (Cancer pagurus L.) from Scottish coastal waters.

Concentrations of cadmium in the hepatopancreas (0.1-61.3 mg kg-1), gonad (0.15-11.0 mg kg-1) and gills (0.2-10.7 mg kg-1) of the edible crab Cancer pagurus L. from 16 sampling sites round the Scottish coast are reported, and compared with published elevated concentrations in crabs from the Orkney Islands. Geographical variations in the distribution of cadmium between organs indicate that the dietary uptake of cadmium is predominant in northern mainland and Orkney crabs, but that uptake from the water is more important in the south of Scotland. Mean dissolved cadmium concentrations in eastern coastal water increase from approximately 10 ng dm-3 in northern waters to approximately 25 ng dm-3 in the south. It seems likely that a regional contamination of the environment by cadium of geological origin occurs in the extreme north coast of Scotland, and in the Orkney and Shetland areas.

Animals↗
PubMed1984

Home births in England and Wales, 1979: perinatal mortality according to intended place of delivery.

A survey was carried out of all 8856 births occurring at home in England and Wales in 1979. Of these births, 67% had been booked for delivery at home, 21% had been booked for delivery in hospital, 3% had not been booked, and for 9% the intended place of delivery was unknown. The perinatal mortality varied almost 50-fold according to the intended place of delivery, ranging from 4.1/1000 births in those booked for delivery at home to 196.6/1000 unbooked births. Deliveries that occurred at home but had been booked for a hospital consultant unit were associated with a perinatal mortality of 67.5/1000. Births that had been booked for delivery at home included the smallest proportion of babies of low birth weight: 2.5% weighed 2500 g or less compared with 18% of those booked for consultant units and 29% of those not booked. Within these low birthweight groups there were noticeable differences in perinatal mortality; births booked to occur at home had the lowest mortality and unbooked births had the highest. Perinatal mortality among babies who weighed more than 2500 g was generally low irrespective of the intended place of delivery; the only exception was in babies whose delivery had not been booked. In all groups perinatal mortality was considerably higher in nulliparous than parous women. Women booking a delivery at home are clearly a selected group, and some may have been transferred to hospital during labour and were thus not included in the survey. Nevertheless, these data suggest that the perinatal mortality among births booked to occur at home is low, especially for parous women.

Adult↗