Liu J., Zheng B., Aposhian HV., Zhou Y., Chen ML., Zhang A., Waalkes MP (Organic carcinogenesis Section, Laboratory of Comparative Carcinogenesis, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina , USA):Chronic arsenic poisoning from burning high-arsenic containing coal in guizhou, China. Environ Hlth Perspect, 110(2), 2002, 119-122.[31 Ref]

Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through air and food. Here we report the health effects of arsenic exposure from burning high arsenic containing coal in Guizhou, China. Coal in this region has undergone mineralization and thus produces high concentrations of arsenic. Coal is burned inside the home in open pits for daily cooking and crop drying, producing a high concentration of arsenic in indoor air. Arsenic in the air coats and permeats food being dried producing high concentrations in food; however, arsenic concentrations in the drinking water are in the normal range. The estimated sources of total arsenic exposure in this area are from arsenic contaminated food (50-80 percent), air (10-20 percent), water (1-5 percent), and direct contact in coal mining workers (1 percent). At least 3,000 patients with arsenic poisoning were found in the Southwest Prefecture of Guizhou, and approximately 200,000 people are at risk for such overexposures. Skin lesions are common, including keratosis of the hands and feet, pigmentation on the trunk, skin ulceration, and skin cancers. Toxicities to internal organs, including lung dysfunction, neuropathy, and nephrotoxicity, are clinically evident. The prevalence of hepatomegaly was 20 percent, and cirrhosis, ascites, and liver cancer are the most serious outcomes of arsenic poisoning. The Chinese government and international organizations are attempting to improve the house conditions and the coal source, and thereby protect human health in this area.

Guo HR (Graduate Institute of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan, ROC, Taiwan): Cancer risk assessment for arsenic exposure through oyster consumption. Environ Hlth Perspect, 110(2), 2002, 123-124. [23 Ref]

Risk is assessed on the basis of assumption, but this practice might not be well received by the general public. To avoid miscommunication, the assumption should be stated clearly in reporting the results. Recently, a report on an assessment of the cancer risk associated with consumption of oysters caused a panic among consumers in Taiwan and produced significant effects on related industries. A group of researchers measured the arsenic content in oysters in the Taiwan area and conducted a cancer risk assessment accordingly. The results, published in research article in an international journal, included a lifetime cancer risk estimate of 5.10/10-4 as calculated based on the assumption that a person consumes oysters with the highest arsenic level (19.3 mg/g dry weight) at the highest rate (1.39 g/day) for 30 years. A national newspaper in Taiwan translated part of the article and published results that focused on the finding that this estimate was more than 500 times higher than what would be considered acceptable by the U.S. Environmental Protection Agency. As a result, most consumers stopped purchasing oysters, and the related industries suffered substantial losses. The newspaper's omission of the key assumption in the risk assessment and the extreme assumptions made in the risk assessment led to this tragedy. This event demonstrated the importance of careful communication of risk assessment results.

Zeitz P., Orr MF., Kaye WE (Epidemiology and Surveillance Branch, Division of Health Studies, Agency for Toxic Substances and Diseases Registry, Atlanta, Georgia, USA): Public Health consequences of mercury spills: hazardous substances emergency events surveillance system, 1993-1998. Environ Hlth Perspect, 110(2), 2002, 129-138. [54 Ref]

We analyzed data from states that participated in the Hazardous Substances Emergency Evans Surveillance (HSEES) system maintained by the Agency for Toxic Substances and Diseases Registry to describe the public health consequences of mercury releases. From 1993 through 1998, HSEES captured 406 events in which mercury was the only substance released. Schools and universities, private residences, and health care facilities were the most frequent locations involved in mercury events, and human error was the contributing factor for most of the releases. Fourteen persons experienced adverse health effects as a result of the release. An additional 31 persons had documented elevated levels of mercury in the blood. No fatalities resulted. Evacuations were ordered in 90 (22 percent) of the events, and the length of evacuation ranged from 1 hr to 46 days. Mercury spills have a significant public health impact and economic burden. Some actions that could potentially lessen the consequences of mercury spills are to switch to mercury-free alternatives, train people in the safe handling and disposal of mercury, and keep mercury securely stored when it is necessary to have it on hand.

Hwang KY., Lee BK., Bressler JP., Bolla KI., Stewart WF., Schwartz BS (Division of Occupational and Environmental Health, Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA): Protein kinase C activity and the relations between blood lead and neurobehavioral function in lead workers. Environ Hlth Perspect, 110(2), 2002, 133-138. [54 Ref]

At picomolar concentrations, lead activates protein kinase C (PKC). This activation has been implicated in the neurotoxicity of lead. No prior study has evaluated the association of PKC activity with neurobehavioral function in humans. The purpose of this study was to determine whether PKC activity is associated with neurobehavioral function of modifies the relationship between blood lead levels and neurobehavioral test scores. In this cross-sectional study of 212 current lead workers in the Republic of Korea, we assessed blood lead levels, neurobehavioral test scores, and PKC activity. PKC activity was determined by measuring the levels of phosphorylation of three erythrocyte membrane proteins (spectrin and the 52-KDa and 48 KDa subunits of band 4.9), using an in vitro back-phosphorylation assay. When linear regression was used to control for confounding variables, blood lead was a significant predictor of decrements in performance on tests of psychomotor function, manual dexterity, and executive ability. In linear regression models, back-phosphorylation levels were not associated with neurobehavioral test scores, but when dichotomized at the median, back-phosphorylation levels modified the relationship between blood lead and test scores. For spectrin and the 52kDa and 48-kDa subunits of band 4.9, 5, 2, and 5 of 14 interaction terms, respectively, had associated p-values < 0.10, all with positive signs, indicating that blood lead was associated with worse test scores only in subjects with lower back-phosphorylation levels. These data indicate that blood lead levels are associated with decrements in neurobehavioral test scores, mainly in the domains of manual dexterity and sychomotor function, but only in subjects with lower in vitro back-phosphorylation levels, which is equivalent to higher in vivo PKC activity. We hypothesize that subjects with higher PKC activity in the presence of lead may be more susceptible to the health effects of lead.

Lee K., Xue J., Geyh AS., Ozkaynak H., Leaderer BP., Weschler CJ., Spengler JD (University of California, School of Medicine, Davis, California, USA): Nitrous acid, nitrogen dioxide, and ozone concentrations in residential environments. Environ Hlth Perspect, 110(2), 2002, 145-149. [26 Ref]

Nitrous acid (HONO) may be generated by heterogenous reactions of nitrogen dioxide and direct emission from combustion sources. Interactions among nitrogen oxides and ozone are important for outdoor photochemical reactions. However, little is known of indoor HONO levels or the relationship between residential HONO, NO2, and O3 concentrations in occupied houses. Six-day integrated indoor and outdoor concentrations of the three pollutants were simultaneously measured in two communities in Southern California using passive samples. The average indoor HONO concentration was 4.6 ppb, compared to 0.9 ppb for outdoor HONO. Average indoor and outdoor NO2 concentrations were 28 and 20.1 ppb, respectively. Indoor O3 concentrations were low (average 14.9 ppb) in comparison to the outdoor levels (average 56.5 ppb). Housing characteristics, including community and presence of a gas range, were significantly associated with indoor NO2 and HONO concentrations. Indoor HONO levels were closely correlated with indoor NO2 levels and were about 17 percent of indoor NO2 concentrations. Indoor HONO levels were inversely correlated with indoor O3 levels. The measurements demonstrated the occurrence of substantial residential indoor air, indoor/outdoor concentrations, nitrogen dioxide, nitrous acid, ozone, residence.

Moonan CW., Sarasua SM., Campagna D., Kathman SJ., Lybarger JA., Mueller PW (Agency for Toxic Substanes and Disease Registry, Division of Health Studies, Health Investigations Branch, Atlanta, Georgia, USA): Effects of exposure to low levels of environmental Cadmium on renal biomarkers. Environ Hlth Perspect, 110(2), 2002, 151-155. [40 Ref]

We conducted a study among residents of a small community contaminated with heavy metals from a defunct zinc smelter and residents from a comparison community to determine whether biologic measures of cadmium exposure were associated with biomarkers of early kidney damage. creatinine adjusted urinary cadmium levels did not differ between the smelter and comparison communities; thus we combined individuals from both communities (n = 361) for further analyser. The overall mean urinary cadmium level was low, 0.26, ug/g creatinine, similar to reference values observed in the U.S. general population. For children ages 6-12 years, urinary concentration of N-acetyl-B-D-glucosaminidase (NAG), alanine aminopeptidase (AAP), and albumin were positively associated with urinary cadmium, but these associations did not remain statistically significant after adjusting for urinary creatinine and other potential confounders. For adults ages 18 or older, urinary concentration of NAG, AAP, and albumin were positively associated with urinary cadmium. The associations with NAG, AAP, and albumin were positively associated with urinary cadmium, but these associations did not remain statistically significant after adjusting for urinary creatinine and other potential confounders. For adults ages 18 or older, urinary concentration of NAG, AAP, and albumin were positively associated with urinary cadmium. The associations with NAG and AAP but not with albumin remained statistically significant after adjusting for creatinine and other potential confounders. We found a positive dose-effect relationship between levels of creatinine adjusted urinary cadmium and NAG and NAP activity, and statistically significant differences in mean activity for these two enzymes between the highest (>= 1.0 ug cadmium/g creatinine) and the lowest (< 0.25 ug cadmium/creatinine) exposure groups. The findings of this study indicate that biologic measures of cadmium exposure at levels below 2.0 ug/g creatinine may produce measurable changes in kidney biomarkers.

Markaverich B., Mani S., Alejandro MA., Mitchell A., Markaverich D., Brown T., Trippe CV., Murchison C., Malley B., Faith R (Center for Comparative Medicine, Baylor College of Medicine, Houston, Texas, USA): A novel endocrine-disrupting agent in corn with mitogenic activity in human breast and prostatic cancer cells. Environ Hlth Perspect, 110(2), 2002, 169-. [69 Ref]

Housing adult rats on ground corncob bedding impedes male and female mating behavior and causes acyclicity in females. The suppressive effects on ovarian cyclicity are mimicked by a mitogenic agent purified from the ground corncob bedding material (corn mitogen; CM) which stimulates the proliferation of estrogen receptor (ER) positive (MCF-7 cells) and ER negative (MDA-MD-231 cells) breast cancer cells. Purified CM does not compete for [3H] estradiol binding to ER or nuclear type II sites, and its effects on MCF-7 breast cancer cell proliferation are not blocked by the antiestrogen ICI-182,780. These results suggest that the active component is unlikely to be a phytoestrogen, bioflavonoid, mycotoxin, or other known endocrine disrupting agent that modifies cell growth via ER or type II [3H] estradiol binding sites. CM also stimulates the proliferation of PC-3 human prostatic cancer cells in vitro, and the growth rate of PC-3 cell xenografts is accelerated in nude male mice housed on ground corncob as opposed to pure cellulose bedding. Consequently, this endocrine disrupting agent in ground corncob bedding may influence behavioral and physiologic reproductive response profiles and malignant cell proliferation in experimental animals. Fresh corn (kernels and cob) or corn tortillas also contain CM, indicating that human exposure is likely, consequently, CM and/or related mitogens in corn products may influence human health and development.

Hong YC., Lee JT., Kim H., Ha EH., Schwartz J., Cristian DC (Department of Occupational and Environmental Medicine, Inha University College of Medicine, Incheon, Korea): Effects of air pollutants on acute stroke mortality. Environ Hlth perspect, 110(2), 2002, 187-191. [36 Ref]

The relationship between stroke and air pollution has not been adequately studied. We conducted a time-series study to examine the evidence of an association between air pollutants and stroke over 4 years (January 1995-December 1998) in Seoul, Korea. We used a generalized additive model to regress daily stroke death counts for each pollutant, controlling for seasonal and long term trends and meterologic influences, such as temperature, relative humidity, and barometric pressure. We observed an estimated increase of 1.5 percent (95 percent confidence interval (C1), 1.3-1.8 percent) and 2.9 percent (95 percent Cl, 0.3-5.5 percent) in stroke mortality for each interquartile range increase in particulate matter < 10 um aerodynamic diameter (PM 10) and ozone concentrations in the same day. Stroke mortality also increased 3.1 percent (95 percent Ci, 1.1-5 percent) for nitrogen dioxide, 2.9 percent (95 percent CI, 0.8-5.0 percent) for sulfur dioxide, and 4.1 percent (95 percent CI, 1.1-7.2 percent) for carbon monoxide in a 2-day lag for each interquartile range increase in single pollutant models. When we examined the associations among PM10 levels stratified by the level of gaseous pollutants and vice versa, we found that these pollutants are interactive with respect to their effects on the risk of stroke mortality. We also observed that the effects of PM10 on stroke mortality differ significantly in subgroups by age and sex. We conclude that PM10 and gaseous pollutants are significant risk factors for acute stroke death and that the elderly and women are more susceptible to the effect of particulate pollutants.

Pehkonen SO., Zhang Q (Dept. of Chemical and Environmental Engineering, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore): The degradation of organophosphorus pesticides in natural waters: A critical review. Crit Rev Environ Sci Technol, 32(1), 2002, 17-72. [99 Ref][Rev]

Organophosphorus pesticides (OPs) have been widely used throughout the world since the decline in the use of organochlorine pesticides in the 1960s and 1970s. They are less persistent in the environment when compared with organochlorine pesticides and thus pose less long-term health risks to nontarget aquatic organisms and humans. However, in recent years several governmental agencies, including the USEPA, have started to reconsider the wide use of organophosphorus pesticides due to concern about their effects on the central nervous systems of humans, children in particular. This review discusses the fate of organophosphorus pesticides in the aquatic environment via processes such as adsorption, hydrolysis, oxidation, and photochemical degradation. Furthermore, the breakdown products of OPs are discussed , as new research has indicated that the products of degradation can be very harmful as well and because relatively little research has been carried out on comprehensive product identification.

Kanamori T., Inoue H., Iwata Y., Ohmae Y., Kishi T (National Research Institute of Police Science, 6-3-1, Kashiwanoha, Kashiwa-shi,Chiba 277-0882, Japan): In vivo metabolism of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in the rat: identification of urinary metabolites. J Anal Toxicol, 26(2), 2002, 61-66. [8 Ref]

The in vivo metabolism of 4-bromo-2,5-dimethoxyphenethylamine (2C-B), a ring-substituted psychoactive phenethylamine in the rat was studied. Male Wistar rats were administered 10 mg/kg of 2C-B hydrochloride orally, and 24 h urine fractions were collected. After enzymatic hydrolysis of the urine samples, the metabolites were extracted by liquid-liquid extraction and analyzed by gas chromatography-mass spectrometry. 2-(4-Bromo-2,5-dimethoxyphenyl)-ethanol, 4-bromo-2,5-dimethoxyphenylacetic acid, 2-(2-hydroxy-4-bromo-5-methoxyphenyl)-ethylamine, 2-(2-methoxy-4-bromo- 5-hydroxyphenyl)-ethylamine, 1-acetoamino -2-(2-hydroxy- 4-bromo-5-methoxyphenyl) ethane, and 1-acetoamino-2- (2-methoxy-4-bormo-5- hydroxyphenyl)-ethane were identified as 2C-B metabolites. These findings suggest that at least two metabolic pathways for 2C-B are operative in rats. The first pathway leads to the corresponding aldehyde metabolite by deamination, which is subsequently reduced or oxidized, to give the corresponding alcohol and carboxylic acid metabolites. The second pathway leads to the corresponding 2-O-desmethyl or 5-O-desmethyl metabolites in which the amino group is subsequently acetylated.

Baker CK., Sams R (KL Maddy Equine Analytical Chemistry Laboratory University of California, Davis, California, USA): Detection of morphine in blood and urine samples from horses administered poppy seeds and morphine sulfate orally. J Anal Toxicol, 26(2), 2002, 81-86. [13 Ref]

The objective of this study was to determine if the administration of poppy seeds to horses would result in detectable concentrations of morphine in urine and blood samples, as has been shown to occur in humans. In this study blood and urine samples were collected following administration of poppy seeds and morphine sulfate orally to four horses. Urine samples were subjected to enzyme linked immunosorbent assay (ELISA) for the presence of morphine. All urine samples testing positive by ELISA, as well as plasma samples collected after administration of the 10-g doses of poppy seeds, were analyzed by gas chromatography-mass spectrometry for the presence of morphine. Morphine was detectable in the plasma samples for at least 4 h after administration of 10 g of poppy seeds. Morphine was detectable in urine samples for up to 24 h after administration of 10 g, 5 g, and 1 g of poppy seeds and 426.7 ug of morphine as morphine sulfate. The results of this study indicate that horses that consume or are administered poppy seeds may have detectable concentrations of morphine in their urine and plasma for hours after administration.

Hernandez F., Pitarch E., Serrano R., Gaspar JV., Olea N (Analytical Chemistry,Dept. Experimental Sciences, University Jaume 1, 12004 Castellon, Spain): Multiresidue determination of endosulfan and metabolic derivatives in human adipose tissue using automated liquid chromatographic cleanup and gas chromatographic analysis. J Anal Toxicol, 26(2), 2002, 94-103. [32 Ref]

A multiresidue method based on normal-phase liquid chromatography (LC) cleanup and gas chromatography-electron capture detection-mass selective detection (GC-ECD-MSD) analysis has been developed for the determination of endosulfan and its main metabolic derivatives in human adipose tissue. Analyses were extracted by dissolving the fat samples in n-hexane, and the hexanic extracts were directly injected onto the silicagel column of the automated LC cleanup system. Purified LC extracts were analyzed by GC-ECD or GC-MSD, without any solvent exchanges of preconcentration steps. The high efficiency of the high-performance liquid chromatographic cleanup for the elimination of fats allowed to reach detection limits for all analytes at low nanograms-per-gram concentration levels. The optimized overall analytical procedure was applied to 18 selected human mammary adipose and abdominal fat tissue samples. p,p'-DDE, hexachlorobenzene, and B-HCH were the most frequently detected compounds, and residues of endosulfan sulfate and ether were also found in several samples. All findings were confirmed by an additional GC-MS-MS analysis of the LC sample extracts.


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