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Biomedical subjects

M Gochfeld

Publications and source records attributed to M Gochfeld.

At least 91 records · Page 5Linked to original sources
PubMed1994

Implications of the Occupational Safety and Health Administration's bloodborne pathogen standard for the occupational health professional.

On December 6, 1991. The Occupational Health and Safety Administration (OSHA) issued its final regulation concerning occupational exposure to bloodborne pathogens (29 CFR 1910.1030). OSHA has determined that workers in a variety of settings face a significant health risk as the result of occupational exposure to blood and other body fluids. The pathogens that are of the most concern include human immunodeficiency type 1 (HIV) and hepatitis B virus (HBV). OSHA concludes that the hazard can be minimized via engineering and work practice controls, personal protective equipment, HBV vaccination, training and education, and appropriate use of signs and labels. Occupational health professionals, including physicians, nurses, industrial hygienists, and safety officers, are faced with the challenge of writing and periodically updating exposure control plans that are unique to their settings, as well as advising colleagues in other settings. They are charged with identifying the appropriate at-risk groups within their workplace, and providing them with the appropriate training to enable employees to understand the rationale for the safety procedures that prevent exposures to blood-borne pathogens. This review of HIV/HBV articles pertinent to the occupational setting analyzes six topics including: (1) occupational risk of transmission of HIV, (2) occupational risk of transmission of HBV, (3) special concerns of dental practices, (4) risk of HIV/HBV outside the hospital, medical, or dental office setting, (5) legal and ethical issues involved in HIV testing, and (6) the United States Public Health Service postexposure HIV/HBV prophylaxis/treatment recommendations.

Blood-Borne Pathogens↗
PubMed1993

Lead and behavioral development in young herring gulls: effects of timing of exposure on individual recognition.

Lead exposure early in life affects behavioral, physiological, and intellectual development in humans and other animals. Recognition of parents or other caregivers and eventual bonding are essential aspects of behavioral development. In this paper young herring gulls, Larus argentatus, were used to examine the effect of timing of lead exposure on individual recognition behavior and development. Each of 60 1-day-old herring gull chicks was randomly assigned to a control group or to one of three treatment groups that received a single dose of lead nitrate solution (100 mg/kg) at Day 2 or 6 of age or the same total dose divided in thirds on Day 2, 4, and 6. Matched controls were injected with isotonic saline on the same schedules. Variations in individual recognition of human attendants were largely explained by age and status (lead versus control), and some variation was explained by day of injection (exposure regime). Using a feeding paradigm, the percentage responding to their caretaker compared to another person was higher (70% versus 38%), and occurred earlier in controls compared to lead-injected birds. Lead-injected birds required longer to respond initially, took longer to choose, moved less distance per time, and took longer to eventually reach the food. These results were all significant by GLM models and Kruskal-Wallis tests. Among lead-injected birds there was a disjunction of effect related to dosing schedule: birds injected on Day 6 chose more correctly but were slower to respond, indicating that these behavioral traits were differentially affected by timing of exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Heavy metal and selenium levels in feathers of young egrets and herons from Hong Kong and Szechuan, China.

Several species of herons and egrets frequently nest in colonies in areas where humans also concentrate. Since the birds feed on intermediate-sized fish that themselves concentrate pollutants, they can be used not only to assess the levels of contaminants in avian tissues but as indicators of contaminants in the environment. The concentration of heavy metals and selenium in the breast feathers of fledgling black-crowned night herons Nycticorax nycticorax and Chinese pond herons Ardeola bacchus from the Tu Jing Yan heronry outside Chengdu, Szechuan Province in China; and from fledgling black-crowned night heron, little egret Egretta garzetta, great egret Egretta alba and cattle egret Bubulcus ibis from the Mai Po heronry in Hong Kong, were determined. Breast feathers were also collected from adult great egrets in Hong Kong. Adult great egrets had significantly higher levels of all heavy metals than did young great egrets. There were no significant interspecific differences in metal levels among the young at Szechuan China, except for chromium (pond herons had higher levels). There were significant differences among the young nesting at Hong Kong for all metals examined. Great egrets had lower, and night herons had higher, levels of lead than the other young. Night herons also had the highest levels of cadmium, manganese, and selenium compared to the other young. Great egret chicks had the lowest mercury levels, while little egret had the highest levels. Lead levels for all the birds in both Hong Kong and Szechuan were among the highest in the world, and this was attributed to the continued use of leaded gasoline.

Animals↗
PubMed1993

Heavy metal and selenium levels in endangered wood storks Mycteria americana from nesting colonies in Florida and Costa Rica.

Colonially-nesting birds often nest in coastal areas, along rivers, or near other bodies of water that also are potentially polluted from industrial, agricultural or urban development. The levels of heavy metals and selenium were examined in the feathers of young wood storks Mycteria americana nesting in Northeastern Florida and from adult and young storks nesting on the Tempisque River on the west coast of Costa Rica. There were no significant yearly differences among the chicks from Costa Rica. Concentration of mercury, cadmium, and lead were significantly higher in the chicks from Florida compared to those from Costa Rica. Adult wood storks at Costa Rica had significantly higher levels of lead, cadmium, selenium, and manganese than young from the same colony.

Age Factors↗
PubMed1993

Fishing in contaminated waters: knowledge and risk perception of hazards by fishermen in New York City.

Risk perception studies show that people may underestimate significant risks while overestimating others. Further, government agencies may assume the public becomes aware of risks when the agency has issued advisories, when in reality a segment of the population remains unaware of these warnings. This article reports on a survey of people fishing on the catchment basins of Jamaica Bay Wildlife Refuge in New York City. Of the 154 groups interviewed, only 19% believed the waters or fish were contaminated or unsafe, despite state warnings to the contrary. Fishermen made nearly five visits per month, and ate an average of three fish a week, (remaining fish were eaten by their families) and fish were usually fried. Most people believed the fish were safe to eat, or that they could recognize if one was spoiled. Thus, most people were ignoring the health advisories on consuming fish from these waters. We suggest that these fishermen are unaware of health advisories, or ignore them because the fishing situation is familiar, voluntary, pleasurable, and has not resulted in their illness. Since they believe they can determine if the fish are bad from smell and appearance, they have changed their own analysis from the unknown (chronic, delayed risks from toxics) to the known (immediate illness), lowering their perceived risk, but not the actual risk.

Animals↗
PubMed1993

Age- and gender-related variations in the activities of drug-metabolizing and antioxidant enzymes in the white-footed mouse (Peromyscus leucopus).

The effects of aging on the activities of drug-metabolizing enzymes and antioxidant enzymes were studied in male and female White-Footed mice (Peromyscus leucopus) at ages of 6, 8, 12, 18, 24, 30, 36, and 48 months. Male mice had significantly higher liver microsomal cytochrome P450 (P450) content and NADPH:cytochrome P450 oxidoreductase (P450 reductase) activities than females at all age groups. Many of the P450-dependent enzyme activities were also generally higher in males. Female mice showed age-dependent decreases in P450 content and the activities of P450 reductase, pentoxyresorufin O-dealkylase (PROD) and N-nitrosodimethylamine demethylase (NDMAd) in the liver from 6 to 24 months; while, the males showed an age-dependent decrease only for the liver PROD activity from 6 to 24 months. The old males (30-month old) appeared to have significantly higher activities for 6 beta-, 2 beta-, 16 alpha- and 16 beta-testosterone and androstenedione formation than the middle-aged (6- to 18-month old) and very old (48-month old) males. Females showed age-dependent decreases for the formation of 6 beta-, 2 beta-, 16 alpha- and 16 beta-testosterone in liver microsomes from 6 to 24 months. Lung microsomes from 6- and 8-month old males had much higher activities of ethoxyresorufin O-deethylase (EROD) and PROD than older males. The total NNK alpha-hydroxylation activities changed in the same pattern as lung microsomal EROD and PROD activities in both male and female mice. The activities of several phase II drug-metabolizing enzymes: glutathione S-transferase (GST), DT-diaphorase, sulfotransferase and UDP-glucuronosyl-transferase (UDPGT) did not show any significant age-dependent changes, with the possible exception that the GST activity in males decreased from 18 to 36 months. Males had about 3-fold higher UDPGT activities than females among all age groups. Glutathione peroxidase activities were drastically lower in old and very old males, and 6 to 24 months old males had significantly higher activities than the corresponding females. In females, superoxide dismutase activities decreased linearly to extremely low levels as mice aged. Catalase activities showed a tendency for increase with age in males. In conclusion, some P450-dependent activities and antioxidant enzymes, but not phase II drug-metabolizing enzymes, showed age-dependent changes; and most of these changes occur from 6 to 24 months. The demographic attributes of the White-Footed mouse are well-suited for physiological and biochemical studies of aging and can complement the more standard laboratory mouse model with its typical two year life span.

Age Factors↗
PubMed1992

Heavy metal and selenium concentrations in black skimmers (Rynchops niger): gender differences.

Most studies of heavy metals and selenium have not examined or have failed to find differences in concentrations in the tissues of birds as a function of size or sex. Heavy metal and selenium concentrations were analyzed in breast feathers of adult black skimmers Rynchops niger, a species with marked sexual size dimorphism in which males average 35% heavier than females. Females had significantly higher concentrations of lead and cadmium than males, but there were no gender differences in mercury, selenium, chromium, manganese, and copper despite the marked sexual dimorphism in body size. There were no significant correlations of bird weight or wing length and metal and selenium concentrations, and few correlations among metal and selenium concentrations in the feathers.

Animals↗
PubMed1992

Heavy metal and selenium levels in young cattle egrets from nesting colonies in the northeastern United States, Puerto Rico, and Egypt.

Colonially-nesting species of herons and egrets breed mainly in coastal areas, along rivers or near other large bodies of water. Such areas are also preferred for human development, exposing nesting birds to various pollutants. From 1989-1991, the concentrations of heavy metals and selenium were studied in the feathers of fledgling cattle egrets Bubulcus ibis, a terrestrially-feeding insectivore, from New York and Delaware in the northeastern United States, from Puerto Rico, and from Egypt. There were geographic differences in the concentrations of lead, mercury, cadmium, manganese, selenium, and chromium in the feathers of these egrets. Lead levels were 41 times higher in the feathers of cattle egrets from Cairo compared to the other sites. This difference was attributed to the continuing use of leaded gasoline and the dense automobile traffic in Cairo. However, other differences remain unexplained. Similarly, levels of chromium and manganese were also higher in Cairo than at any other sites. Cadmium levels were similar at all places except for higher levels in eastern Puerto Rico. Mercury concentrations were twelve times higher in the feathers of cattle egrets at Aswan compared to Cairo. In Puerto Rico, we also compared levels in adult cattle egrets with young and found higher concentrations of mercury and manganese, but lower concentrations of selenium in the adults. Using feathers from young cattle egrets is a potentially sensitive tool for biomonitoring for metals, especially lead, since they reflect the local area surrounding the breeding colony.

Animals↗
PubMed1992

Temporal scales in ecological risk assessment.

The process of human health risk assessment (HRA) was formalized in 1983 by the National Research Council to include hazard identification, dose-response analyses, exposure assessment and risk characterization. Risk assessment for ecologic endpoints is emerging as a new discipline. Although environmental impact statements have been conducted for many years, ecologists, managers and policy makers are beginning to formalize the process in terms of risk, and are adapting the HRA paradigm to ecological risk assessment (ERA). In this paper it is suggested that the temporal scales of the two processes differ, and that these differences should be incorporated in ecological risk assessment. Even when HRA techniques are applied to a single non-human species there are temporal variations including: (1) different and often variable life spans, (2) unpredictable lengths of lifestages and different metamorphic stages, and (3) indeterminate growth in some species. When these differences are considered for multispecies assemblages, the impact on the food web will result in exposures of differing magnitudes affecting different species. The challenges for ERA include developing general principles for estimating or predicting exposure to critical life stages of the dominant species in an ecosystem, and establishing the appropriate temporal scales for predicting impacts or evaluating outcomes.

Ecology↗
PubMed1992

Trace element distribution in growing feathers: additional excretion in feather sheaths.

The use of feathers is a non-invasive and repeatable method for biomonitoring trace element levels in birds and their ecosystems. Trace element levels were examined in different parts of growing flight feathers from young common terns (Sterna hirundo) to determine distribution of heavy metals and selenium, potential bias from using partially grown feathers, and whether additional heavy metals and selenium are excreted in feather sheaths that are sloughed before feathers are usually sampled. Lead and mercury levels were significantly higher in the distal fully formed portion of the growing feather (with no residual blood supply) compared to the proximal, growing portion of the feather with a residual blood supply, but no significant differences were evident for cadmium and selenium. These results suggest that using partially grown feathers underestimates the amount of lead and mercury in fully formed feathers and that higher levels of lead and mercury are sequestered in feathers than are present in the blood at any one time. Significantly higher concentrations of lead and cadmium, and significantly lower levels of mercury were in the sheath compared to the whole feather blade. These data suggest that birds excrete more lead and cadmium during molt than previously thought.

Animals↗
PubMed1992

Comparison of lead levels in bone, feathers, and liver of herring gull chicks (Larus argentatus).

Bone, feathers, and liver were analyzed for lead in herring gull chicks (Larus argentatus) of two different ages. The highest levels were found in the bone, evidence of chronic exposure. No differences were found within the bones. Differences occurred between different bones, with the ribs having twice the amount of lead than any other bone. These studies indicate that type of bone affects lead levels; thus researchers should clearly state which parts of which bones are examined. It is also suggested that for humans consistent location should be used for analysis by in vivo X-ray fluorescence.

Age Factors↗
PubMed1992

Effects of washing fiddler crabs (Uca pugnax) following an oil spill.

An oil spill on 2 January 1990 in New Jersey resulted in premature emergence of fiddler crabs Uca pugnax from their underground burrows. Live fiddler crabs that emerged on the surface were collected and behavioral changes were compared between those that were washed with freshwater and those that were not washed. Locomotion, aggression, balance, and burrowing behavior were examined. Unwashed crabs improved significantly on only one of twelve behavioral tests, while washed crabs improved in four tests relating to movement, defensive behavior, and burrowing. The washed crabs showed the greater improvement on ten of twelve tests while unwashed crabs showed greater improvement for two tests. Washed crabs also showed greater improvement in their ability to find and to construct their own burrows. These experiments indicate that oil removal improves the behavioral performance of crabs, and suggests that under some circumstances the immediate flushing of salt marsh creeks by uncontaminated tidal waters may decrease behavioral effects on crabs.

Journal Article↗
PubMed1992

Medical surveillance and screening in the workplace: complementary preventive strategies.

The terms medical surveillance and medical screening have sometimes been used interchangeably in the occupational medicine literature. Recently attempts have been made to redefine these as mutually exclusive, by nesting surveillance under screening or vice versa, by subsuming both under medical monitoring or periodic examinations, or by eliminating use of the term medical surveillance altogether. In this paper I argue that medical surveillance and medical screening represent discrete concepts and approaches and should be viewed as distinct and complementary secondary preventive components of an occupational health program. Medical surveillance refers to the periodic examination of putatively exposed workers, and is therefore a longitudinal approach. Medical screening refers to the cross-sectional testing or evaluation of a group of workers. Biological monitoring, whether defined narrowly or broadly, focuses on exposure to particular toxicants and should serve as a component of medical surveillance (or of medical screening), not as an independent complement to environmental monitoring. Medical surveillance must function in the context of a comprehensive occupational health program that includes industrial hygiene and education and does not in itself suffice as a comprehensive occupational health program. It is useful to clarify these terms because some of the ethical issues as well as medical controversies over their utility arise from a misunderstanding of what constitutes medical surveillance and how it should be applied.

Cross-Sectional Studies↗
PubMed1992

Exposure assessment for heavy metal ingestion from a sport fish in Puerto Rico: estimating risk for local fishermen.

Sport or subsistence fishermen sometimes underestimate the risks from eating local fish and distrust authorities regarding potential hazards from fish. We report on lead, cadmium, selenium, and mercury levels in snook, locally called robalo (Centropomus spp.), consumed by local fishermen in Puerto Rico, who ate up to 23 fish/wk. Median levels (in ppb, dry weight) for muscle, adipose, and liver ranged from 683 to 780 for lead, 37 to 600 for cadmium, 50 to 146 for mercury, and 361 to 3986 for selenium. Lead levels were similar in all tissues, and selenium and cadmium levels were highest in the liver. Mercury was higher in muscle than in liver. Computing exposure via ingestion for the average fisherman indicated that if one were to consume robalo throughout the year one would be exposed in excess of the EPA Reference Dose (RfD) for mercury. Using a widely accepted maximum consumption of 200 g/d for fishermen yielded hazard indices (daily consumption/RfD) below 1 for all four metals, with a value approaching 1 for mercury in adults, and over 1 for 16-kg children. The possibility that in certain localities and cultures sport or subsistence fishermen may consume fish at levels substantially above 200 g/d should be investigated in performing risk assessments, particularly outside the continental United States.

Adipose Tissue↗
PubMed1992

Metal levels in regrown feathers: assessment of contamination on the wintering and breeding grounds in the same individuals.

Birds are useful indicators of environmental contamination because they are relatively large, conspicuous, top predators in food chains. However, concentrations of contaminants in a bird's tissues reflect the bird's exposure over wide temporal and spatial scales. Birds are most useful as monitors of exposure when these scales are known. In this paper we report concentrations of lead, cadmium, mercury, and selenium in breast feathers of common terns (Sterna hirundo) and roseate terns (S. dougallii) trapped during incubation at breeding colonies in New York and Massachusetts. Terns arrived on the breeding grounds with breast feathers grown on their wintering grounds, and regrew certain feathers that were plucked for analysis. The regrown feathers were themselves plucked, and both sets of feathers were analyzed. For roseate terns at Cedar Beach and common terns at both sites there was a significant increase in mercury levels in the feathers grown on the breeding grounds compared to those grown on the wintering ground. The differences in mercury were far greater at Bird Island than at Cedar Beach. Selenium levels at Cedar Beach were higher for the regrown feathers than the initial feathers for roseate terns, but not for common terns. Lead and cadmium levels were not significantly different at either site for either species. These results suggest that terns are exposed to significantly higher levels of mercury in the northeastern United States than they are in the wintering grounds in South America.

Animals↗
PubMed1992

Survival and reproduction in Peromyscus leucopus in the laboratory: viable model for aging studies.

White-footed mice Peromyscus leucopus reared in our laboratory from wild-caught parents lived at least to 5.5 years. Once past weaning, over 80% of the mice lived at least until two years. Females maintained a constant weight whereas the weight of males increased until four years and decreased thereafter. At four-years of age both sexes bred successfully with mates of the same age, but had lower success with younger mice. Some males and females reproduced at five years of age.

Aging↗
PubMed1991

Lead, mercury, and cadmium in feathers of tropical terns in Puerto Rico and Australia.

Levels of lead, cadmium, and mercury were examined in breast feathers of terns nesting on offshore islets near Culebra, Puerto Rico and on Michaelmas Cay and Heron Island on the Great Barrier Reef, Australia. Levels of all metals in these tropical terns were predicted to be lower than those of terns nesting in temperate regions, because the tropical species feed offshore of non-industrial areas where contamination should be less than for temperature-nesting species that feed in inshore estuaries near industrialized areas. This prediction was not supported by the evidence. In Puerto Rico, lead and cadmium levels were highest in bridled tern (Sterna anaethetus), and mercury levels were highest in sooty (S. fuscata) and roseate tern (S. dougallii). In Australia, levels of lead and mercury were higher in black noddy (A. minutus) and lower for sooty tern; and cadmium levels were highest for brown noddy (A. stolidus) and sooty tern, and lowest for black noddy. Metal levels for the tropical terns nesting in Puerto Rico and Australia generally were not lower than levels reported for temperate-nesting or mainland nesting birds (except for mercury in Australia).

Animals↗