Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Body Burden”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed1981

Phenobarbital treatments lower DDT body burden in rhesus monkeys.

Decreased DDT, DDD, DDE in blood and DDA in urine followed phenobarbital treatments (10 mg/kg/day, 11 days, intramuscular (im)) in three male rhesus monkeys (Macaca mulatta). Animals were fed DDT diets containing up to 500 ppm DDT during a 3-year period. Induction of liver monooxygenases was confirmed by reduced in vivo antipyrine plasma half-life and increased in vitro oxidation rates of dihydroisodrin, p-nitroanisole and benz(alpha)pyrene by homogenates of liver obtained from closed needle biopsy. Chlorohydrocarbon blood levels significantly decreased during the induction period (days 1-11). Concentrations on day 28 were at or below pre-DDT exposure levels. Urine DDA gradually decreased in all monkeys from days 16 to 28.

Animals↗
PubMed2006

New evidence on variations of human body burden of methylmercury from fish consumption.

Epidemiologic studies commonly use mercury (Hg) level in hair as a valid proxy to estimate human exposure to methylmercury (MeHg) through fish consumption. This study presents the results yielded by a complete data set on fish consumption habits, Hg levels in edible fish resources, and corresponding Hg accumulation in hair, gathered in three distinct communities of eastern Canada. For one of these communities, the average hair Hg concentration was 14 times less than the expected value based on calculated daily oral exposure and current knowledge of MeHg metabolism. This finding could be explained by differences in specific genetic characteristics and/or interactive effects of other dietary components.

Animals↗
PubMed1984

Biochemical effects and decreased body burden of cyclopentanone by extended vapour inhalation.

Male Wistar rats exposed intermittently to cyclopentanone vapour at 50, 100 or 300 p.p.m. 6 hrs daily 5 days a week for 1 to 15 weeks showed brain and perirenal fat solvent concentrations which correlated to the exposure although they decreased at the later stages of the experiment. Cyclopentanone caused almost no effects on liver drug metabolizing enzymes or aldehyde dehydrogenase activities while an early increase in the kidney 7-ethoxycoumarin O-deethylase was found after 1 week without a concomitant increase in the cytochrome P-450 content. This effect was abolished later so that an enhancement was found only at the highest exposure level after 15 weeks. Postmitochondrial fractions isolated from liver of exposed animals metabolized cyclopentanone more actively than controls after 15 weeks.

Adipose Tissue↗
PubMed1985

Low level benzene exposure in Sweden: effect on blood elements and body burden of benzene.

Measurements for benzene exposure were performed for different work places. In addition, breath benzene concentrations were measured in different occupations in order to establish toxico-kinetics of benzene in man; chromosomal aberrations in lymphocytes of exposed workers were also examined. Smoking appears to result in a large increase in benzene concentration in exhaled breath. The smoke from one cigarette contains 60-80 micrograms of benzene. It was found that exposure levels of 10 ppm are rather uncommon among workers handling gasoline or gasoline equipment. It was concluded that the gasoline load of road tankers cannot be responsible for chromosome changes of the driver, as milk truck drivers showed the same changes. These results did not prove that benzene was the cause of the observed changes. Smoking is the confounding factor, with a potency of at least the same order of magnitude as benzene. In addition, our present knowledge about mechanisms of benzene is not sufficiently developed to permit quantitative conclusions as to the human health risks.

Air Pollutants, Occupational↗
PubMed1999

Analysis of lead body burden in Turkey.

Here we report the results of pilot screening for the environmental lead contamination in Turkey. Lead blood concentrations were determined in 342 subjects from 17 cities. The mean lead blood concentration, 3.65 +/- 1.66 micrograms/dl, is much lower than the values reported previously. People smoking tobacco and driving motor vehicles had elevated concentrations of lead in blood. There was also a moderate relationship between the urban population size and the lead in blood values, but no differences were observed, that could be related to distinct geographical locations. Motor traffic was assumed to be the main source of lead pollution in the urban environment in Turkey, and the low lead blood levels were linked to the reduction of lead additives in gasoline, in 1989. Although at present, the environmental lead contamination does not pose a considerable threat to public health, in the near future, when the motorization rate and gasoline consumption will possibly double or triple, the lead content in gasoline might need to be further reduced.

Adolescent↗
PubMedDate not supplied

Potential pathways and exposure to explain the human body burden of organochlorine compounds: a multivariate statistical analysis of human monitoring in Würzburg, Germany.

By means of multivariate statistical analysis of human monitoring in the vicinity of Würzburg it is examined whether the organochlorine levels in blood data of 309 persons can in part be explained by pollution from outdoor and/or indoor air. Although diet is the main source for intake this study concentrated on the remaining sources. Using 12 personal and geographical variables, which describe some aspects or components of indoor or outdoor exposure, the quantities of the different pathways for the intake are calculated and shown. Besides the impact of the indoor air, which can be pointed out for intake at the workplace for some PCB-congeners, also the hypothesis of the existence of an intake from outdoor air for some organochlorine compounds cannot be rejected. Here, the origin is the spatial variation of the pollution, which can be directly traced back to micro-climatic processes, local relief conditions, and the functional set-up of the town.

Air Pollution↗
PubMed1982

Body burden of polychlorinated biphenyls among persons employed in capacitor manufacturing.

In an effort to assess exposure among workers engaged in capacitors manufacture, PCB concentration was determined in plasma (290) and adipose tissue (61). In general, males had higher concentrations of PCBs than females. The correlation of plasma concentration (1-546 ppb) of the more highly chlorinated PCBs, which had been used in past, with total duration of employment suggested accumulation over time. The gc-ec pattern of these PCB peaks was, in most cases, characteristic of exposure to a PCB mixture with 54% chlorine. The less highly chlorinated PCBs, di-, tri-, and tetrachlorobiphenyls, were the source of current exposure, and were observed in concentrations of 6-2530 ppb in plasma. Higher exposure occurred among persons with direct contact with PCBs in jobs such as capacitor filling. Adipose tissue concentrations, for both the more highly chlorinated PCBs (1-165 ppm) and lower chlorinated PCBs (0.6-414 ppm), were proportional to those in plasma.

Adipose Tissue↗
PubMed1994

Influence of the common human delta-aminolevulinate dehydratase polymorphism on lead body burden.

delta-Aminolevulinate dehydratase (ALAD) is the second enzyme in the heme biosynthesis pathway. ALAD is a zinc metalloenzyme, and its inhibition by lead substitution for zinc is one of the most sensitive indicators of blood-lead accumulation, a measure of recent lead exposure. Stoichiometry calculations indicate that a significant portion of blood lead is stored in ALAD. Human ALAD exhibits a charge polymorphism, with about 20% of Caucasians expressing the rarer ALAD2 allele. Human ALAD1 and ALAD2 cDNAs and the 16-kb ALAD gene have been cloned and sequenced. A simple polymerase chain reaction test has been established and validated for determining ALAD genotypes. Two population studies have indicated that lead-exposed individuals with the ALAD2 allele have blood-lead levels about 10 micrograms/dl greater than similarly exposed individuals carrying only the ALAD1 allele. Ongoing work is directed toward determining the biochemistry underlying the allele-specific accumulation of blood lead, and toward determining the contribution of human ALAD genotype to lead accumulation in other tissues in transgenic mouse models and to final lead deposition in bone in both mouse and man.

Animals↗
PubMedDate not supplied

Sport fish consumption and body burden levels of chlorinated hydrocarbons: a study of Wisconsin anglers.

Sport-caught fish consumption is the major source of polychlorinated biphenyls (PCBs) exposure for the general population. To assess this and 2,2'-bis-(p-chlorophenyl)-1,1-dichloroethylene (DDE) exposure, we surveyed 801 Wisconsin anglers for fishing and consumption habits and comprehension of and compliance with the Wisconsin fish consumption health advisory. The mean annual number of sport-caught fish meals was 18. Seventy-two percent of anglers were familiar with the health advisory and 57% had changed their fishing or fish consumption habits as a result of the advisory. The mean PCB serum congener sum level for 192 anglers was 2.2 micrograms/l (range = nondetectable to 27.1 micrograms/l); mean DDE was 6.3 micrograms/l (range = nondetectable to 40.0 micrograms/l). Statistically significant positive Spearman correlations were observed between sport-caught fish meals and PCB and DDE sera levels (R = .21 and .14, respectively) and between kilograms of fish caught and PCB sera levels (R = .25). These results demonstrate that anglers may provide a population for assessment of PCBs and DDE associated morbidity and mortality.

Adult↗
PubMed1990

Routes of chloroform exposure and body burden from showering with chlorinated tap water.

While there is an awareness of the need to quantify inhalation exposure from showers, the potential for dermal exposure to organic contaminants in showers has not been appreciated or explored. To establish routes of environmental exposure from showers, comparisons of the concentration of chloroform in exhaled breath after a normal shower with municipal tap water were made with those after an inhalation-only exposure. The postexposure chloroform breath concentrations ranged from 6.0-21 micrograms/m3 for normal showers and 2.4 to 10 micrograms/m3 for inhalation-only exposure, while the pre-exposure concentrations were all less than the minimum detection limit of 0.86 micrograms/m3. According to an F-test, the difference between the normal shower and the inhalation-only exposures was considered significant at a probability of p = 0.0001. Based on the difference, the mean internal dose due to dermal exposure was found to be approximately equal to that due to the inhalation exposure. The effect of the showering activities on the concentration of chloroform shower air was examined by comparing air concentrations during a normal shower with the air concentrations obtained when the shower was unoccupied. The F-test showed that there is no significant difference between the two sets of data.

Air Pollutants↗
PubMed2001

Effects of molting and environmental factors on trace metal body-burdens and hemocyanin concentrations in the American lobster, Homarus americanus.

Hemocyanin concentrations in the hemolymph of marine crustacea are dependent on the molt cycle and on environmental conditions. Studies in our laboratories have found that hemocyanin levels in blue crabs are reduced after ecdysis and under conditions of environmental stress (Engel, Brouwer, & McKenna, 1993. Hemocyanin concentrations in marine crustaceans as a function of environmental conditions. Marine Ecology Progress Series, 93, 233-244). We have extended those studies to include the American lobster, Homarus americanus. Hemolymph and digestive gland tissues from Long Island Sound lobsters were analyzed for hemocyanin, copper, and zinc during different stages of the molt cycle. Hemocyanin, copper and zinc in the hemolymph were highest in premolt stages (D1-D4), and lowest in the postecdysal papershell stages (B1-B2). Concomitantly, copper in digestive glands decreased significantly following ecdysis, but no significant changes in the metals bound to metallothionein (MT) were observed. Copper-MT was the predominant form throughout the molt cycle, presumably because lobsters were obtained from copper-contaminated areas. To examine the effects of environmental factors, intermolt lobsters were collected from locations of different environmental quality along the Atlantic coast, and were analyzed for hemocyanin and trace metals. In general, animals from areas with a history of contamination showed the highest hemocyanin concentrations.

Animals↗
PubMed2005

Body burdens of polybrominated diphenyl ethers among urban anglers.

Polybrominated diphenyl ethers (PBDEs) have been widely used in the United States and worldwide as flame retardants. Recent PBDE production figures show that worldwide use has increased. To determine whether fish consumption is a source of PBDE exposure for humans, a cross-sectional epidemiologic study of New York and New Jersey urban anglers was conducted during the summers of 2001-2003. Frequency of local fish consumption was assessed by questionnaire, and blood samples for PBDE analysis were collected from 94 anglers fishing from piers on the lower Hudson River and Newark Bay. We analyzed PBDEs by gas chromatography-isotope dilution-high-resolution mass spectrometry. The congeners found in anglers' serum at the highest concentrations were, by International Union of Pure and Applied Chemistry numbers, BDE-47, BDE-153, and BDE-99. Anglers reporting consumption of local fish had higher, but nonstatistically significantly different, concentrations of PBDEs than did anglers who did not eat local fish. For some congeners (BDE-100 and BDE-153), we observed moderate dose-response relationships between serum PBDE levels and frequency of reported fish intake. These findings suggest that consumption of locally caught fish is not a major route of human exposure for this study population.

Animals↗
PubMed1984

Dose-response analysis of cadmium in man: body burden vs kidney dysfunction.

The primary objective of this study was to develop dose-response relationships of cadmium in human beings. In vivo measurements of kidney, liver, urine, and blood cadmium, and urinary levels of beta 2-microglobulin and total protein were obtained in 82 industrially exposed workers and 30 control subjects. The values of 200 micrograms/g creatinine for urinary beta 2-microglobulin and 250 mg/g creatinine for urinary total protein were used to define the upper limit for normal kidney function. Forty-one of the cadmium workers (18 active, 23 retired) were classified as having abnormal kidney function; all control subjects had normal kidney function. Most workers with Cd above 70 ppm in the liver were judged to have some evidence of kidney abnormalities. The dose-response relationship for liver cadmium for the actively employed workers could be described by a linear logistic regression model: (Formula: see text) where p is the individual's probability of having kidney dysfunction. The loss of cadmium from the kidney following dysfunction prohibited a direct logistic analysis of the kidney cadmium data. However, when the linear relationship between kidney and liver cadmium for the subjects with normal kidney function was combined with the logistic equation for the liver, a predicted-response curve was obtained for the kidney. The logistic models predict a 50% probability of having kidney dysfunction at 38.4 mg for the kidney and 42.3 ppm for the liver, respectively.

Body Burden↗
PubMed1998

[Influence of exposure to mercury, arsenic and antimony on body burden--a biomonitoring study].

Part of the northern Palatinate region in Germany is characterized by elevated levels of mercury, arsenic and antimony in the soil due to the presence of ore sources and former mercury mining activities. Today, the region is characterized by housing and agriculture. In a biomonitoring study, 218 residents (age 1-89 years) were investigated for a putatively increased absorption of these elements from the environment. 76 non-exposed subjects (age 2-84 years) of a region in south lower Saxony (Germany) were chosen as a reference group. Urine and scalp hair samples were obtained as surrogates to determine the internal exposures to mercury, arsenic and antimony. In the northern Palatinate subjects slightly, yet presumably not hazardous, elevated arsenic contents in urine and scalp hair could be correlated to an increased arsenic content in the soil. On the other hand, the results did not show a correlation between the mercury and antimony contents in the soil of the housing area and those in urine and hair. Urinary mercury contents were correlated with the total amalgam area in both study groups. Mercury contents in scalp hair and arsenic contents in urine were correlated with the consumption of seafood. Surprisingly, the geogenically non-exposed reference subjects showed significantly higher internal exposures to arsenic and antimony in urine and scalp hair. However, data of both groups correspond to normal range reference data described by others.

Adolescent↗
PubMed2001

Quantitative evaluation of urinary porphyrins as a measure of kidney mercury content and mercury body burden during prolonged methylmercury exposure in rats.

Changes in urinary porphyrin excretion patterns (porphyrin profiles) during prolonged mercury exposure are attributable to mercury accumulation in the kidney and to consequent effects of Hg2+ on renal porphyrin metabolism. In the present study, we evaluated the quantitative relationship of urinary porphyrin concentrations to mobilizable renal mercury content, using the metal chelator 2,3-dimercapto-1-propanesulfonic acid (DMPS) to modulate kidney mercury levels. Rats exposed to methylmercury hydroxide (MMH) at 10 ppm in drinking water for 6 weeks were treated with up to 3 consecutive doses of DMPS (100mg/kg, ip) at 72-h intervals. Consistent with previous findings, the concentrations of pentacarboxyl- (5-) and copro- (4-) porphyrins and of an atypical porphyrin specific to mercury exposure, precoproporphyrin, were significantly elevated in urine of MMH-exposed rats, compared with that of rats exposed to distilled water (dH2O) for the same period. Consecutive DMPS treatments of MMH-exposed rats significantly decreased kidney concentrations of total, as well as Hg2+ and CH3Hg+ species, and promoted increased urinary mercury excretion. Concomitantly, DMPS treatment decreased both kidney and urinary porphyrin concentrations, consistent with depletion of renal mercury levels. Regression analyses demonstrated a high correlation (r approximately 0.9) between prechelation urinary porphyrins and postchelation urinary mercury levels and also between prechelation urinary porphyrins and prechelation kidney mercury concentrations. These findings demonstrate that urinary porphyrin concentrations relate quantitatively to DMPS-mobilizable mercury in the kidney and, therefore, serve as a biochemical measure of renal mercury content.

Animals↗
PubMed1991

[Evaluation of equivalent body burden in the thyroid for the people of Poland on results of 131I absorption after the disaster in Czernobyl. Determination of thyroid blockade with potassium iodide].

An assessment of effectiveness of the administering of single dose of stable iodine in Poland on the reduction of 131I doses in thyroid has been performed. 5-compartment model of metabolism of iodine developed by Johnson has been used to evaluate predicted levels of stable iodine and 131I content in thyroid and commitment dose equivalent H50 for different doses of stable iodine and various age and sex group population. The measured values of 131I concentration in air and in milk and standard values for milk and food consumption and inhalation rate as well as metabolic parameters were used. Theoretical calculations showed that administering of stable iodine on 1986-04-28, 1986-04-29, 1986-04-30 and 1986-05-01 could have reduced committed dose equivalent H50 form ingestion with inhalation pathway by about 44%, 40%, 26%, 12% respectively. On the basis of measured 131I activity in the thyroid for inhabitants from different districts in Poland (1400 measurement) committed dose equivalents were determined and analysis of radiation hazard from 131I were performed. In the most contaminated regions of Poland average H50 doses for children 1-5 and 5-10 years old are close to 50 mSv (permissible level for population) and maximal doses exceed this limit four times. These maximal doses occurred for about from 5% inhabitants from these area. In the moderate and low contaminated regions of Poland the average doses are fivefold and tenfold less respectively.

Air Pollutants, Radioactive↗
PubMed2006

Maternal body burdens of methylmercury impair survival skills of offspring in Atlantic croaker (Micropogonias undulatus).

Methylmercury (MeHg), the organic form of mercury, bioaccumulates easily through the food chain. Fish in high trophic levels can accumulate substantial levels of MeHg and transfer it to their developing eggs. Here, the effects of maternally derived MeHg on the planktonic larval stage of Atlantic croaker were investigated. Adult Atlantic croaker were fed MeHg-contaminated food at three levels: 0, 0.05, and 0.1 mg kg(-1) day(-1) for 1 month. Fish were then induced to spawn and MeHg levels in the eggs were measured (0.04-4.6 ng g(-1)). Behavioral performance of exposed and control larvae was measured at four developmental stages: end of yolk absorption (yolk), end of oil absorption (oil), and 4 and 11 days after oil absorption (oil+4 and oil+11). Behaviors analyzed included survival skills related to foraging and predator evasion: routine behavior (rate of travel, active swimming speed, net-to-gross displacement ratio, and activity) and startle response to a visual and a vibratory stimulus (responsiveness, reactive distance, response distance, response duration, average response speed, and maximum response speed). Maternally transferred MeHg induced concentration-dependent effects on survival skills. Statistical and simulation models applied to predict the ecological consequences of the behavioral effects suggested that maternal transfer of MeHg may substantially lower survival of planktonic stage larvae compared to unexposed larvae. These results also imply that larvae of top predatory fish species, such as blue marlin, may suffer mortality through maternal transfer of MeHg.

Animals↗
PubMed1989

Dose and time effects of combined exposure to lead and ethanol on lead body burden and some neuronal, hepatic and haematopoietic biochemical indices in the rat.

Ethanol (1, 2 or 5 g kg-1) and lead (0.55 g l-1 in drinking water) were given either alone or in combination for 4 months to rats. The uptake of lead in tissues, some lead-sensitive variables, the levels of biogenic amines in different brain regions, hepatic lipid peroxidation, glycogen and blood glucose concentrations were measured. Ethanol or lead when given alone inhibited the activity of blood delta-aminolevulinic acid dehydratase (ALAD). The co-administration of 5 g kg-1 but not 1 or 2 g kg-1 ethanol significantly enhanced the lead-induced inhibition of blood delta-ALAD activity and the elevation of delta-aminolevulinic acid (ALA) excretion. Co-exposure to lead and ethanol (5 g kg-1) produced a more pronounced increase in hepatic lipid peroxidation and blood glucose level than either ethanol or lead alone. This combination also caused a significant increase in the dopamine (DA) contents of striatum, midbrain and pons medulla, norepinephrine (NE) contents in midbrain and 5-hydroxytryptamine (5-HT) contents of hypothalamus, striatum, midbrain and pons medulla over levels produced by lead alone. However, the level of NE in hypothalamus decreased upon co-administration. The uptake and retention of lead was significantly higher in blood, liver, kidney and brain in animals co-exposed to lead and 5 g kg-1 ethanol. Blood and kidney lead was also increased by 2 g kg-1 ethanol. The results suggest that prolonged and heavy consumption of alcohol may increase the toxicity of lead.

Animals↗