Archives of environmental health最新文献

The authors investigated the impact of effluents from a car battery manufacturing plant in Nnewi, Nigeria, on water, soil, and food qualities. The authors analyzed heavy metals mercury, arsenic, lead, cadmium and nickel in tap and cassava waters, soil, dried cassava tuber, and edible fruit samples from the company, using an atomic absorption spectrophotometer. Other parameters the authors analyzed include pH, electrical conductivity (EC), salinity (SAL), total hardness (TH), biological oxygen demand (BOD), volatile and non-volatile solids, and bacterial and fungal loads of the soil samples. Results show that lead had the highest concentration in all the samples, with the soil samples having the highest lead concentration (38-12 ppm, 102 ppm) and the water samples having the lowest (0.02-0.20 ppm). Mercury had the lowest concentration (<0.0002 ppm) in all the samples. Soil sample B had the highest concentration of all the metals tested. Cassava water had higher levels of EC, SAL, TH, BOD, and volatile and nonvolatile solids, but lower pH than tap water. Bacterial loads were higher than fungal loads in all the soil samples. Because there was moderate contamination of the environment by some of the metals studied, with lead being exceptionally high and above the specified international standards, the authors recommend control measures to reduce lead exposure to the local populace within and around this industry.

Mercury is considered to be one of the most harmful metals. Studies of the so-called normal mercury content in human internal organs, blood, and urine can be useful for assessment of the level of environmental exposure and also for legal and medical expert opinions. The examination encompassed 75 autopsies of inhabitants of southern Poland (50 male and 25 female) investigated at the Institute of Forensic Research in Kraków, Poland, between the end of 1998 and the beginning of 2001. Samples of internal organs were homogenized and digested with nitric and sulfuric acids. Determination of total mercury was performed by the use of cold vapor atomic absorption spectrometry. The following results (range and mean, in ng/g wet weight) were obtained: brain (n = 49) 0-14.2, 2.3 +/- 1.9; liver (n = 69) 2.6-55.0, 15.5 +/- 9.5; kidney (n = 63) 3.2-170, 35.9 +/- 31.7; heart (n = 4) 1.2-2.8, 2.2 +/- 0.75; spleen (n = 17) 2.4-9.6, 4.0 +/- 1.8; lung (n = 22) 1.8-9.1, 3.3 +/- 1.8; stomach (n = 48) 0-4.5, 2.0 +/- 1.0; small intestine (n = 32) 0-14.2, 2.8 +/- 2.7; large intestine (n = 13) 0 - 23.9, 5.2 +/- 7.2; blood (n = 35) 0 6.5, 1.6 +/- 1.2; urine (n = 14) 0 2.6, below detection limit. The above mentioned levels of mercury are similar to those reported by other Polish authors, but are lower than those determined in normal Korean and Japanese organs.

The effect of blood cadmium (Cd), which reflects not only Cd body burden but also recent Cd exposure and communicates with fetal blood in the placenta, on newborn size at birth was investigated. Blood Cd of 55 mothers from Toyama, Japan, at 30-32 gestational weeks was measured using a flameless atomic absorption spectrophotometer. The relationship between blood Cd and newborn size was analyzed after adjustment for gestational age and maternal build. A significant inverse correlation was found between infant height and maternal blood Cd. After adjustment for gestational age and maternal weight at 30-32 gestational weeks, the significant inverse relationship between maternal blood Cd and infant height was shown using the multiple regression analysis. Newborn size might be influenced by maternal blood Cd levels to which infants may be exposed during gestation.

Children residing in Philadelphia, Pennsylvania, who were enrolled in a clinical trial of oral chelation therapy (n=73) were studied to determine the effects of a follow-up professional lead dust cleaning of their homes 18 mo after an initial cleaning and commencement of therapy. Home dust lead levels were determined from dust-wipe specimens collected from the kitchen and playroom floors, and from a playroom windowsill, prior to, immediately following, and 3 and 6 mo after the second cleaning. Children's blood lead levels were assessed at 3-mo intervals before and after the follow-up cleaning. Professional cleaning produced immediate decreases in dust lead levels; however, dust lead re-accumulated to precleaning levels within 3-6 mo. Frequent, repeated cleanings may be required if blood lead or dust lead levels are to be reduced and sustained at low levels in urban homes.

Concern about health risks from sulfur dioxide (SO2) pollution prompted a health risk assessment for residents of the heavily polluted industrial region of South Durban, South Africa. The U.S. Environmental Protection Agency health risk assessment model was used to evaluate health effects for individuals in 4 age groups on the basis of data for a 3-yr period, from 1997-1999. Under normal exposure conditions, the level of risk was low (Hazard Quotient < 1); only under the worst-case scenario (exposure 24 hr/day) was there a significant risk of developing health effects. Inasmuch as these results are contrary to the popularly held belief that residents have a high risk of developing SO2-related respiratory diseases under normal exposure conditions, future studies should more thoroughly investigate exposure patterns and verify the authors' assumption that indoor SO2 levels are zero.

Chlorine and potassium cresylate spilled from a train wreck forced evacuation of nearly 1000 people in and near the town of Alberton, Montana, in 1996. Because respiratory and other symptoms persisted in this population, neurobehavioral and pulmonary functions were evaluated in a cohort of exposed vs. unexposed individuals. Ninety-seven subjects were tested 7 wk after exposure. Three years later, 36 of the original subjects were retested, along with 21 new patients exposed in the same incident. These 57 were compared with 22 unexposed individuals. Twenty-six neurobehavioral functions were tested, and spirometry was performed on each subject. At 7 wk postexposure, patients showed significant differences in 5 neurobehavioral functions (i.e., balance, simple reaction time, abnormal visual quadrants, vocabulary, and information), compared with the unexposed individuals recruited in 1999. Patients' Profile of Mood States scores and frequencies of 35 symptoms were also elevated, compared with the unexposed group. At 3 yr postexposure, patients exhibited differences in 7 additional neurobehavioral functions (i.e., choice reaction time, balance with eyes open, color errors, visual fields, Culture Fair, and verbal recall). Respiratory symptoms were increased, but pulmonary functions did not change. Exposure to chlorine and potassium cresylate produced neurobehavioral impairments that have been observed to increase across 3 yr. Spills in heavily populated areas could injure thousands, overwhelming medical facilities.

Lignite contains various trace-metal natural radioactive contaminants. In the Eordea Basin, the most important lignite field in Greece, the authors conducted a proportional mortality ratio (PMR) study that compared the mortality rates of individuals who lived in the basin vs. a control group who resided in the city of Kilkis, over a 30-yr period. The following information was used in the study: (a) municipal registrations of deaths from neoplasms during the period from 1971 to 2000, and (b) detection of radioactive substances in samples obtained from excised lungs of individuals living in Eordea Basin who suffered from neoplasm. The corresponding registrations of deaths from neoplasm of the inhabitants of Kilkis, a city located outside the Eordea Basin, formed the control group. A diachronic increase of the PMR was detected as a result of neoplasms and, particularly, as a result of lung cancer in Eordea Basin. However, the above ratio did not exceed the corresponding PMR recorded in Kilkis. In 20 lung samples obtained from patients who had lived in Eordea Basin, and in 19 lung samples from patients in Kilkis, the activity of the radionuclides of uranium and thorium radioactive decay series, potassium-40, and cesium-137 was not higher than expected. No statistically significant difference was found between the inhabitants of the 2 regions, thus it was concluded that the increase in respiratory-system neoplasms was likely associated with the high prevalence of smoking among the regions' inhabitants. In future studies, a longer observation period and examination of more cases will be necessary to further investigate a possible association between radionuclides and lung neoplasms in the Eordea Basin.