Relation of dietary inorganic arsenic exposure and urinary inorganic arsenic metabolites excretion in Japanese subjects

Inorganic arsenic (InAs) is a ubiquitous metalloid that has been shown to exert multiple adverse health outcomes. Urinary InAs and its metabolite concentration has been used as a biomarker of arsenic (As) exposure in some epidemiological studies, however, quantitative relationship between daily InAs exposure and urinary InAs metabolites concentration has not been well characterized. We collected a set of 24-h duplicated diet and spot urine sample of the next morning of diet sampling from 20 male and 19 female subjects in Japan from August 2011 to October 2012. Concentrations of As species in duplicated diet and urine samples were determined by using liquid chromatography-ICP mass spectrometry with a hydride generation system. Sum of the concentrations of urinary InAs and methylarsonic acid (MMA) was used as a measure of InAs exposure. Daily dietary InAs exposure was estimated to be 0.087 µg kg^?1 day^?1 (Geometric mean, GM), and GM of urinary InAs+MMA concentrations was 3.5 ng mL^?1. Analysis of covariance did not find gender-difference in regression coefficients as significant (P > 0.05). Regression equation Log ₁₀ [urinary InAs+MMA concentration] = 0.570× Log ₁₀ [dietary InAs exposure level per body weight] + 1.15 was obtained for whole data set. This equation would be valuable in converting urinary InAs concentration to daily InAs exposure, which will be important information in risk assessment.     

Copper and zinc bioavailabilities to ryegrass (Lolium perenne L.) and subterranean clover (Trifolium subterraneum L.) grown in biosolid treated Chilean soils

The purpose of this study was assessing Cu and Zn availabilities in soils amended with a biosolid through the determination of their sequentially extracted chemical forms and their relationship with the contents of these metals in ryegrass (Lolium perenne L.) and subterranean clover (Trifolium subterraneum L.) plant tissues cultivated in a greenhouse using four soils classified as Aquic Xerochrepts and Ultic Haploxeralfs representatives of potential areas for biosolids application in the central zone of Chile. The soils were treated with sewage sludge at a rate of 0 and 30 Mg ha⁻¹. The greenhouse experiment was carried out through a completely randomized block design in a 2 × 4 (biosolid rate × soil) arrangement, considering three repetitions per treatment. The soils used in the greenhouse experiment before and after cultivation, were sequentially extracted with specific reagents and conditions in order to obtain the following fractions: exchangeable, sodium acetate-soluble, soluble in moderately reducing condition, K₄P₂O₇-soluble, soluble in reducing condition, and soluble in strongly acid and oxidizing condition. It was established that Cu and Zn were predominantly found in soils in less available forms, associated to organic matter, oxides and clay minerals. Zinc concentration in ryegrass plants was higher than that found in subterranean clover plants in biosolid-amended soils. Zinc contents in ryegrass shoot and root correlated with the exchangeable, bound-to-carbonate, and bound-to-FeOx metal forms in control soil. Copper and Zn bioavailabilities were estimated through satisfactorily fitted multiple linear regression models, with determination coefficients from 0.77 to 0.99, which showed a positive contribution of the labile metal forms in soils, especially in relation to Zn in both plant species.     

日本在华遗弃化学武器埋藏地调查及其污染处置方法研究

日军二战期间在中国遗弃（留）了大量化学武器,随着埋藏时间的推移,化学武器的弹体腐蚀程度越来越严重,毒气和毒剂泄漏的几率不断增加,因此而造成土壤、水体等环境污染、进而威胁居民生命健康甚至突发性人员伤亡的危险性也在不断加大。本文提出利用低空热红外遥感与三维高密度电法、三维地质雷达等浅层高精度综合物探方法、结合小口径探孔取样...     

苯并[a]芘对马氏珠母贝鳃组织抗氧化酶活性的影响

将马氏珠母贝（Pinctada martensi）暴露于不同质量浓度（1、4和8μg.L-1）苯并[a]芘B[a]P中,检测暴露后第3、7和10天后,马氏珠母贝鳃组织抗氧化酶（超氧化物歧化酶SOD、谷胱甘肽硫转移酶GST和过氧化氢酶CAT）对苯并[a]芘胁迫的生态毒理效应。结果表明：暴露时间为3、7 d时,SOD活性无明显变化,随着暴露时间的延长,SOD活性在第10天时被激活;在胁迫初期,GST活性被激活,随后表现出逐渐降低的趋势,在暴露后10 d,不同质量浓度组GST活性变化趋于稳定。当暴露质量浓度相同时,表现出明显的时—效关系;而CAT活性在第7天被激活,随着时间的延长,高质量浓度（4和8μg.L-1）组表现出先升高后下降的趋势,并表现出一定的时-效关系。SOD、GST和CAT均可作为B[a]P污染的生物标志物,活性变化相对于SOD,GST和CAT对B[a]P的胁迫更加敏感。     

川东高海拔山区红三叶、红三叶─鸭茅和红三叶─黑麦草人工群落生物量的比较研究

红三叶牧草作为一个优良牧草品种，在川东高海拔山区表现尤为突出。本文就红三叶、红三叶─鸭茅和红三叶─黑麦草三个人工群落进行了比较系统的生物量观测，比较了三个群落的总生物量、地上生物量、地下生物量特点，分析了各群落生物量在不同部位的分配情况，垂直空间上的配置，以及各器官在垂直空间上的配置和各个群落的茎、叶、花、立枯在垂直空间上所构成的分布带谱，通过以上分析发现，红三叶─黑麦草群落的总生物量最高，为４６．４７ｋｇ／ｈａ，其中地上部分为２４．５７ｋｇ／ｈａ，而红三叶─鸭茅群落的地下部分最为发达，地下生物量达２４．７４ｋｇ／ｈａ。根据群落生产结构，发现以红三叶为主的人工群落，其生产结构为不规则塔型分布，在离地面２０─４０ｃｍ处，生物量有一个高峰，并且红三叶─黑麦草群落的地上、地下生物量在垂直空间上分布较为均匀，其生产结构较为合理。通过各器官垂直空间分布分析，发现茎主要分布在４０ｃｍ以下，叶量最大是在４０ｃｍ左右，生殖器官最大量在５０ｃｍ附近，并且根据群落的茎：叶：花（穗）：立枯垂直分布带谱可以发现，各个器官在不同层次中所处的地位，而且根据此带谱可以掌握草地的刈割时间和刈割高度。     

Waste separation at home: Are Japanese municipal curbside recycling policies efficient?

Recent studies have predicted that the costs and benefits of curbside recycling programs will vary considerably across municipalities. In this paper, we examine how the characteristics of municipalities are reflected in curbside recycling policies. Our analysis of Japanese municipal data reveals that municipalities implement recycling programs that fit the demographic profiles of their residents. Municipalities with a considerable number of single-recycler households tend to implement simple waste separation programs. The labor market positions of spouses have different impacts on recycling policies. We further find that the municipalities implementing comprehensive recycling programs collect plastic bottles and containers more frequently than do other municipalities. This implies that the municipalities need to take measures to effectively execute comprehensive recycling programs after implementing them.     

中日规范中关于液化和侧向扩流场地桥梁桩基抗震设计考虑之比较

评述了我国液化场地和侧向扩流场地桥梁桩基抗震设计规范.总结了中日两国液化场地和侧向扩流场地桥梁桩基的抗震设计方法与技术细节,阐述了日本规范中液化场地和侧向扩流场地桥梁桩基抗震设计中的液化地基土反力折减系数的确定方法,以及土体液化侧向扩流对桩作用力的计算模式.指出我国规范中在液化和侧向扩流场地桩的抗震分析方法、不同土层分...     

二甲苯、蒽、苯并[α]芘对虾夷扇贝幼贝血清SOD、CAT活性的影响

以虾夷扇贝(Mizuhopecten yessoensis)为受试生物,设置3种不同浓度的二甲苯、蒽、苯并[α]芘处理健康的虾夷扇贝,检测血清中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性变化情况,结果发现:0.01~1.0 mg·L~(-1)的二甲苯、0.002~0.2 mg·L~(-1)的蒽、0.001~0.1 mg·L~(-1)的苯并[α]芘处理6、12 h后,虾夷扇贝血清SOD活性升高,处理12 h后对血清SOD活性诱导率均高于处理6 h的;处理6 h后,血清CAT活性降低,而处理12 h后,血清CAT活性升高;具有显著的剂量-效应关系和时效关系,表明二甲苯、蒽、苯并[α]芘对虾夷扇贝具有氧化胁迫作用,可能导致其氧化损伤。相关性分析发现,3种污染物处理6 h后,血清SOD活性与CAT活性变化呈显著负相关;而处理12 h后,血清SOD活性与CAT活性变化呈显著正相关。上述结果为开展二甲苯、蒽、苯并[α]芘对海洋贝类毒性评价提供基础数据。     

日本青鳉(Oryzias latipes)胚胎和卵黄期仔鱼对镉的 敏感性

物理化学方法对镉的监测忽略了其生物可利用性,生物监测可以有效地弥补这种不足。本研究测试了日本青鳉(Ory-zias latipes)胚胎和卵黄期仔鱼对镉的敏感性。结果表明:日本青鳉胚胎和卵黄期仔鱼的蛋白含量对镉表现出较高的敏感性,卵黄期仔鱼的蛋白含量在4μg·L-1的氯化镉暴露后就出现显著降低;氯化镉对卵黄期仔鱼脊柱畸形的EC50低于国家地表水环境质量标准规定的Ⅱ类水标准;脊柱畸形率与镉浓度之间存在的线性关系,可为定量监测镉污染提供理论依据;脊柱畸形可以在48h之内被4μg·L-1的氯化镉极显著地诱导,因此这种潜在的生物监测模型很有希望应用到水环境污染的快速预警中。通过对国内主要水体中镉污染水平的分析发现,卵黄期仔鱼的蛋白含量变化和脊柱畸形率对部分水体的镉污染可以实现生物监测。因此,利用日本青鳉胚胎和卵黄期仔鱼对低水平镉污染的高度敏感性,能够建立起1种简易廉价并且有效的水环境中低水平镉污染的生物监测模型。     

Differences in the behavior characteristics between Daphnia magna and Japanese madaka in an on-line biomonitoring system

It is important to select suitable organisms to adapt the requirement of di erent environment monitoring purposes. Following our previous study, the behavioral responses of Daphnia magna and Japanese madaka (Oryzias latipes) were investigated and compared under flow-through conditions in an on-line biomonitoring system. The results showed that both D. magna and Japanese madaka had similar biological clock, but the circadian rhythms of Japanese madaka was more clearly recorded than that of D. magna. And the sensitivity of D. magna was about two orders of magnitudes higher than that of Japanese madaka in di erent types of toxic chemicals (dichlorovos, deltamethrin and cadmium chloride). However, when both animals were used in an on-line biomonitoring system, the life span of D. magna was less than 7 days and Japanese madaka could last for more than one month without feeding. Therefore, D. magna was proposed to be a more sensitive bioindicator and was suitable for short term monitoring the pollution events at concentration level closing to the water quality standard, while Japanese madaka was more suitable for the long-term monitoring for accidental discharges.