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231.

Background

Studies on the association of maternal exposure to polychlorinated dibenzo-p-dioxin (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) with decreased birth weight in humans have produced conflicting results. In Japan in 1968, an accidental human exposure to rice oil contaminated with PCDDs, PCDFs, and PCBs, led to the development of Yusho disease.

Objective

The Yusho cohort was used to evaluate the effect of maternal exposure to PCDDs, PCDFs, and PCBs on birth weight.

Methods

Blood samples, obtained from 101 Yusho women (190 births) who gave birth after exposure, were analyzed for congeners of seven PCDDs, ten PCDFs, and four non-ortho PCBs.

Results

Total PCDD TEQ (adjusted beta = − 161.9 g; 95% CI, −265.3 to − 58.6), total PCDF TEQ (adjusted beta = − 105.9 g; 95% CI, −179.5 to − 32.2), and total non-ortho PCBs (adjusted beta = − 178.4 g; 95% CI, −318.3 to − 38.5) levels were inversely associated with birth weight. Significant inverse associations with birth weight were also found for total PCDD TEQ, total PCDF TEQ, and total non-ortho PCB TEQ levels among male, but not female, infants. Significant inverse associations with birth weight were also found for nine congeners among all infants; the adjusted beta coefficients were largest for 1,2,3,6,7,8-HxCDD and smallest for 2,3,4,7,8-PeCDF.

Conclusion

In the setting of exposure to high levels of dioxins, maternal blood levels of PCDDs, PCDFs and PCBs are associated with lower birth weight in Yusho patients. The association exhibited gender-specific differences, as male infants are more susceptible than females to growth restriction induced by in utero dioxin exposures.  相似文献   
232.
Accumulated maternal dioxins are passed onto the fetus and neonate via the placenta and maternal milk. In Japan in 1968, an accidental human exposure to rice oil contaminated with polychlorinated biphenyls (PCBs) and other dioxin-related compounds, such as polychlorinated dibenzofurans (PCDFs), led to development of Yusho oil disease. We investigated differences in blood dioxin concentrations in mother-children pairs affected by the Yusho incident. From 2002 to 2008, blood samples were collected from 26 pairs of Yusho mothers and their children (19 mothers, 26 children). Specific congeners of seven polychlorinated dibenzo-p-dioxins (PCDDs), ten PCDFs, and four non-ortho PCBs were analyzed. The children had significantly lower TEQ concentrations of PCDDs, PCDFs, and coplanar PCBs compared to their mothers. The mother-child difference in blood concentrations varied with the congeners; the largest for 2,3,4,7,8-pentaCDF and the smallest for 1,2,3,4,6,7,8-heptaCDD. The level for 2,3,4,7,8-pentaCDF, which characterizes Yusho oil disease, was approximately 17-30 times higher in the mothers than in the general population, whereas there were no significant differences between children in the formula-fed group and the general population. In contrast, the mean level for 2,3,4,7,8-pentaCDF in the breast-fed group was approximately 1.5 times, (range 0.5-6.5 times) higher than that in the general population. Over 30 years after the Yusho incident, the mean blood dioxin levels in the offspring were only a fraction of the levels in their mothers. This is more consistent with exposure via breast milk than via transplacental transfer in the Yusho incident.  相似文献   
233.
234.
We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho coplanar polychlorinated biphenyls (non-ortho PCBs), and mono-ortho coplanar polychlorinated biphenyls (mono-ortho PCBs) in blood collected between 2002 and 2004 from 195 pregnant women living in Sapporo City of Hokkaido Prefecture, Japan. The present study is one of the few studies in which PCDDs, PCDFs, and dioxin-like PCBs have been measured in the blood of pregnant women. Of the 195 pregnant women, 101 were primipara (mean: 28.8 years) and 94 were multipara (mean: 32.4 years). The arithmetic mean total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs of primiparous and multiparous mothers in Sapporo City were 17.4 (median: 15.7) and 14.0 (median: 13.9)pgTEQ/glipid, respectively, and the concentrations were in the range of 6.6-43.4 and 3.4-28.2pgTEQ/glipid, respectively. In regard to the relationship between the total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in maternal blood and the number of deliveries or age of primiparous and multiparius mothers, the levels of these dioxin-like compounds tended to decrease with increases in the number of deliveries and significantly increased with increasing maternal age in both groups. Furthermore, significant correlations were observed between the total TEQ concentrations of these dioxin-like compounds and the age of primiparae and multiparae. The total TEQ concentration of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs measured in 195 pregnant women has decreased compared to past levels in Japan for the last several decades. The results of the present study have indicated that dioxin contamination in the blood of young women in Japan is continuing to decrease.  相似文献   
235.
Field monitoring was practiced from 2001 to 2003 to evaluate the input (irrigation, atmospheric deposition, and fertilizer application) and the output (uptake and accumulation into the above-ground biomass of rice plants and leaching) of cadmium (Cd) in a contaminated paddy field in Tokyo. The cadmium concentrations of irrigated water, open-bulk precipitation, soil solution (leaching water), rice plants collected at the harvesting stage and the chemical fertilizer and the cow manure compost applied were determined. The Cd flux of each factor was calculated by multiplying the Cd concentration by the volume or mass of the media. The annual input-output balance of Cd in the paddy field in 2001 and 2002 was estimated to be -5.44 [corrected] g ha(-1) and -2.01 [corrected] g ha(-1), respectively, indicating the loss of Cd from the paddy field, although the losses accounted for only 0.24% [corrected] and 0.089% [corrected] of the total amount of Cd in the ploughed layer soil in 2001 and 2002, respectively. Among the factors involved, the input from fertilizers (including manure compost) and the output due to the uptake by rice plants played a major role in the balance. The former largely depended on the types and amounts of fertilizers applied, and the latter on the water management practices in the paddy field, such as flooding and drainage of the surface water.  相似文献   
236.
Effects of perinatal exposure to dioxins, PCBs and organochlorine pesticides on lymphocyte subsets were investigated in the peripheral blood from 101 Japanese infants with approximately 10 months of age. Perinatal exposure to these organochlorine compounds were estimated by their contamination levels in the breast milk of the mothers. Lymphocyte subsets such as CD16+, HLA-DR+, CD4+, CD4+8+, CD8+, CD3+ and CD20+ cells in peripheral venous blood were assessed in a subgroup of 92 infants. Greater exposures to HCE, chlordane and dioxins were significantly associated with the increase in the percentages of CD8+ and CD3+ T lymphocytes and CD4+/CD8+ T cell ratios, respectively. In addition, higher HCH exposure was also associated with a decrease in the percentage of HLA-DR+ T lymphocytes. Furthermore effects of dioxins, DDT and PCBs on the percentage of CD16+ T lymphocyte were more pronounced by the combined exposure of dioxins and PCBs or by the combined exposure of DDT and PCBs. Effects of HCE on the percentages of CD8+ T lymphocyte were also more pronounced by the combined exposure of HCE and chlordane. In conclusion, our study suggests that greater exposures to dioxins, PCBs and organochlorine pesticides determined in this study (except dieldrin) influence the immune system of Japanese infant, although the clinical significance of these changes is uncertain.  相似文献   
237.
Factors affecting the degradation of amoxicillin in composting toilet   总被引:2,自引:0,他引:2  
Kakimoto T  Funamizu N 《Chemosphere》2007,66(11):2219-2224
The biological and non-biological factors that affect the degradation of amoxicillin in the composting process of feces have been investigated. The effect of living bacteria and the enzyme (beta-lactamase) on amoxicillin decay was examined, and our results indicated that the biological effects are likely to be negligible. Consequently, the effect of phosphate, ammonia and pH level as non-biological factors was investigated by monitoring the reduction rate of amoxicillin in phosphate and ammonia buffer solutions with several pH levels. Each reduction rate constant was integrated by a simulation model, and the each calculated amoxicillin reduction profile was compared to the reduction profiles of amoxicillin in the composting process of feces. The calculated results corresponded almost exactly to the experimental profiles. We therefore concluded that the degradation of amoxicillin in a toilet matrix was dependent on the concentration of ammonia, phosphate and hydroxyl ion.  相似文献   
238.
Local residents often oppose some types of facilities because of their negative side effects, even though they are claimed to be necessary for the public good. These facilities are known as locally unwanted-land-uses, and local opposition to them is often referred to as not-in-my-backyard, usually with a pejorative connotation. However, some studies have challenged this conventional view of local opposition. Given these conflicting views, the present article explores how local mobilisation should be evaluated, focusing particularly on distributive justice. First, the study illuminates how different interpretations of distributive justice lead to difference in views on local opposition. Then, by comparing three waste disposal facility cases in Japan, a distinction between cost sharing and cost overlapping cases is illuminated. The study further develops discussions by pointing out the limits of using this distinction to evaluate local opposition movements and provides insights that can contribute to a fuller understanding of siting conflicts.  相似文献   
239.
Objective: Hazard perception (HP) is the ability to identify a hazardous situation while driving. Though HP has been well studied among neurologically intact populations, little is known about the HP of neurologically impaired populations (in this study, stroke patients). The purpose of this study is, first, to investigate the HP of stroke patients and, second, to verify the effect of lesion side (right or left hemisphere) on HP, from the viewpoint of hazard types.

Methods: Sixty-seven neurologically intact age-matched older drivers and 63 stroke patients with valid driver’s licenses conducted a video-based Japanese HP task. Participants were asked to indicate the hazardous events in the driving scenario. These events were classified into 3 types: (1) behavioral prediction hazards (BP), which are those where the cause is visible before it becomes a hazard; (2) environmental prediction hazards (EP), which are those where the ultimate hazard may be hidden from view; and (3) dividing and focusing attention hazards (DF), which are those where there is more than one potential hazard to monitor on approach.Participants also took part in the Trail Making Test (TMT) to evaluate visual information processing speed.

Results: The results showed that the number of responses was significantly fewer for stroke patients than for age-matched drivers for all hazard types (P < .001), and this difference was not affected by lesion side (P > .05). It was also found that stroke patients showed a slower response time than age-matched drivers only for BP (P < .001). The lesion side did not affect response latency (P > .05). Results of the TMT revealed that age-matched drivers completed the task significantly faster than stroke patients (P < .001) and that neither TMT-A nor TMT-B differentiated between patients with left hemisphere damage and patients with right hemisphere damage (P > .05).

Conclusions: Firstly, HP in stroke patients is low compared to age-matched drivers. Secondly, even if stroke patients notice hazards, their response may be delayed in a BP situation, due to a slower visual information processing speed. Thirdly, the lesion side does not appear to affect HP.  相似文献   

240.
In this study, occurrence of 66 PPCPs (pharmaceuticals and personal care products) in liquid and solid phases of sewage sludge was elucidated. The extraction methods for the PPCPs from sludge were newly developed employing Pressurized Liquid Extraction (PLE) and Ultrasonic Solvent Extraction (USE). As an appropriate method, PLE using water (pH2), PLE using methanol (pH4), and USE using mixture of methanol and water (1/9,v/v, pH11) was found most effective because total recovery of most of the PPCPs indicated 40 to 130%. The developed extraction method with previously developed method for liquid phase analysis was applied to field survey at wastewater treatment plants (WWTPs) in Japan. 56 compounds were detected from the primary sludge and 61 compounds were detected from the excess sludge. The concentration was ranged between several ng/g and several μg/g. Solid-water distribution coefficient (Log Kd) ranged between 0.9 L/kg (Caffeine) and 3.7 L/kg (Levofloxacin) for primary sludge and between 1.4 L/kg (Sulpirid) and 4.3 L/kg (Mefenamic acid) for excess sludge.  相似文献   
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