新型蒸压粉煤灰砖厂职业病危害调查及关键控制点分析

目的识别与分析某新型蒸压粉煤灰砖厂职业病危害因素,确定职业病危害的关键控制点。方法按照《工作场所空气中粉尘测定》《工作场所物理因素测量》的要求,对该厂作业场所进行职业卫生学调查和职业病危害因素检测检验。结果粉煤灰砖厂主要存在的职业病危害因素为矽尘、石灰石粉尘、石膏粉尘、噪声。矽尘浓度超标点位包括搅拌机、轮碾机和制砖机,其操作人员接触矽尘的时间加权平均浓度分别为2.26、2.17、5.81 mg/m3,噪声强度超标点位包括球磨机、轮碾机和制砖机,其操作工接触噪声强度分别为86.7、89.3、89.8 dB(A)。该厂存在的职业病危害的关键控制点为球磨机、搅拌机、轮碾机、制砖机等操作岗位。结论在职业病危害防护措施可行、有效的前提下,还应重点加强关键控制点的职业卫生管理和防尘降噪的综合措施。     

In vitro effects of incinerator fly ash on pulmonary macrophages and epithelial cells

Fly ash from a municipal waste incinerator was used as a model for atmospheric particles in order to identify parameters relevant for the induction of adverse health effects. The aim of this study was to compare the biological effects of the total incinerator fly ash (IFA), the soluble and the insoluble fraction with the effects of quartz by in vitro toxicity studies. The previously sized fly ash (< 20 microns) was characterized by elemental composition and particle size distribution. The particles were administered to rat alveolar macrophages (NR8383) and human bronchial epithelial cells (BEAS-2B) at different amounts via the medium. The total IFA and its insoluble fraction were shown to induce cytotoxicity and cytokine release in a dose-dependent manner. The soluble fraction was nearly unable to induce cytotoxicity and TNF-alpha release but showed potent induction of IL-8 release in BEAS-2B cells at increasing concentrations. Quartz caused similar effects compared to IFA in NR8383 but was less effective in BEAS-2B.     

基于工作场所中职业病危害作业分级的某蒸压粉煤灰砖厂新建项目职业病危害控制效果评价

目的通过对某新型蒸压粉煤灰砖厂项目产生的职业病危害因素进行检测和对工作场所中职业病危害作业进行分级,了解其用于职业病危害控制效果评价的可行性。方法采用职业卫生现场调查、检测检验法、定量分级法和职业健康检查法相结合的方法进行评价。结果生产过程中工人接触的主要职业病危害因素为粉尘和噪声,搅拌机、轮碾机等工作场所中粉尘作业分级结果为Ⅰ级,制砖机工作场所中粉尘作业分级结果为Ⅱ级,球磨机、轮碾机、制砖机等工作场所中噪声作业分级均为Ⅰ级。结论现场检测法和工作场所职业病危害作业分级相结合,能够更科学地对建设项目的职业病危害控制效果做出综合评价,为企业职业卫生日常管理工作提供依据。     

Anti-oxidants reduce the acute adverse effects of residual oil fly ash on the frog palate mucociliary epithelium

There is evidence indicating that oxidants play a pivotal role in determining air pollution-dependent lung injury. In the present study we explored the role of oxidants present in ambient particles in causing damage to the mucociliary epithelium. We explored the protective effects of pretreatment with three substances (n-propyl gallate, DL-alpha-tocopherol acetate, and EDTA) on the frog palate exposed to residual oil fly ash (ROFA). The parameters analyzed were mucociliary transport (MCT) and ciliary beating frequency (CBF) after 0, 10, 20, 30, 60, and 120 min of exposure. MCT was decreased significantly by ROFA (P < 0.001), with a significant interaction effect (P = 0.02) between the duration of exposure and treatment with antioxidants. The inhibitory effects on MCT of the substances tested were significantly different (P = 0.002); vitamin E was similar to control (Ringer) and different from all other groups. CBF showed no significant effect of duration of exposure (P = 0.465), but a significant interaction between duration of exposure and treatments was observed (P = 0.011). Significant differences were detected among treatments (P < 0.001), with ROFA and n-propyl gallate at concentrations of 50 microM presenting a short-lived increase in CBF, which was not observed in the remaining groups. The results showed that both MCT and CBF were affected within a short period (100 min) of exposure to ROFA and that the presence of antioxidant substances, such as vitamin E (4 mg/mL) and n-propyl gallate (300 microM), protected against the mucociliary impairment induced by ROFA on the frog palate.     

EDTA对土壤总铬测定的促进作用

[目的]探讨国标法土壤总铬测定中促进剂对测定结果的影响。[方法]提出选择EDTA作为促进剂。[结 果]以EDTA为促进剂可使回收率达89%～108%。[结论]EDTA促进剂可提高测定的准确性。     

The effect of mustard gas on the biological activity of soil

A special group of substances that are very dangerous for the biosphere includes war gases such as mustard gas (bis(2-chloroethyl)sulphide). The influence of mustard gas hydrolysis products (MGHPs) on soil microbiota has been investigated. These substances bear numerous toxic effects on soil microorganisms. They change significantly the number and the specific composition of soil microbiota and inhibit the enzyme activity of soils. The main "ecological targets" of mustard and its hydrolysis products' toxic action have been determined. MGHPs affect the growth and reproduction of soil micromycetes, as well as their morphological and cultural properties. Increase in number and size of mitochondria in the fungal cells is accompanied by increase in dehydrogenases activity. Cell permeability influenced by MGHPs grows in connection with concentration of toxicants. Increase of permeability corresponds to growth of the amount of unsaturated fatty acids. The changes in the fatty acid composition of lipids in the cells of the soil micromycetes display their adaptation to adverse impact of the substances studied. MGHPs and thiodiglycol enhance synthesis of polysaccharides and pigments.     

Field-scale dissipation of tebuconazole in a vineyard soil amended with spent mushroom substrate and its potential environmental impact

The persistence, mobility and degradation of tebuconazole were assessed under field conditions in a sandy clay loam soil amended with spent mushroom substrate (SMS) at two rates. The aim was to evaluate the environmental impact of the simultaneous application of SMS and fungicide in a vineyard soil. SMS is the pasteurized and composted organic material remaining after a crop of mushroom is produced. SMS is generated in increasing amounts in La Rioja region (Spain), and could be used as soil amendment in vineyard soils, where fungicides are also applied in large amounts. The study was carried out in 18 experimental plots (6 treatments and 3 replicates per treatment) over one year. Laboratory experiments were also conducted to verify the changes over time in the adsorption of fungicide by soils and in soil dehydrogenase activity caused by the fungicide and/or SMS. Tebuconazole dissipation followed biphasic kinetics with a rapid dissipation phase, followed by a slow dissipation phase. Half-life (DT50) values ranged from 8.2 to 12.4 days, with lower DT50 for amended soils when compared to the non-amended controls. The distribution of tebuconazole through the soil profile (0-50 cm) determined at 124, 209 and 355 days after its application indicated the higher mobility of fungicide to deeper soil layers in amended soils revealing the influence of solid and dissolved organic matter from SMS in this process. Tebuconazole might be available for biodegradation although over time only chemical or photochemical degradation was evident in surface soils. The results obtained highlight the interest of field and laboratory data to design rational applications of SMS and fungicide when they are jointly applied to prevent the possible risk of water contamination.     

Effect of technical and formulated insecticides on activities of enzymes and levels of adenosine triphosphate in soil

A study was made of the effects of 11 formulated and technical insecticides at 10 µg g^?1 soil on activities of enzymes in a sandy soil. None of the treatments inhibited dehydrogenase and phosphatase activities after 2 and 7 days. Soil nitrogenase was stimulatory with both grades of fonofos. With the exception of the technical chlorpyrifos, fensulfothion, parathion, fenvalerate and with both grades of diazinon and fonofos, insecticides did not affect urease during the initial 7 days. No inhibitory effect on the urease activity was observed after 14 days in any of the treatments. Contents of ATP were significantly greater in technical fonofos treated soils. The results suggested that the effects of both types of insecticides on enzymatic activities were minor in nature and no permanent deleterious effect was observed on enzymatic activities in soil.     

Combined effect of heavy metals and polycyclic aromatic hydrocarbons on urease activity in soil

Actions and interactions between heavy metals (HM)-cadmium, zinc, lead, and polycyclic aromatic hydrocarbons (PAHs)-phenanthrene, fluoranthene, benzo(a)pyrene toward soil urease activity were studied after 7, 14, 21, and 28 days of exposure under controlled conditions. The experimental approach was based on the uniform design. Ten different contamination conditions were studied simultaneously, with 10 concentration levels for each pollutant. Data treatment was essentially based on the multiple regression technique. The results showed that Zn interacted more easily with PAHs than Pb or Cd. On the first 7 days of incubation, zinc alone reduced the urease activity more significantly than any other pollutants and no significant interactions between PAH and HM were observed. From 14 to 21 days of incubation, the interaction between Zn and benzo(a)pyrene decreased the soil urease activity. At 14 days, the interaction between Zn and phenanthrene was antagonistic (less than additive), while at 21 days it was synergistic (more than additive). At 28 days, the interaction between phenanthrene and fluoranthene was synergistic. This study indicated that the combined effect of PAH and HM on soil urease activity depends largely on the incubation time. Uniform design appears to be a good method for investigating the combined effect of PAH and HM.     

泰兴市人群冠心病现患情况及危险因素研究

为了解泰兴市人群冠心病现患情况和危险因素,对35岁以上20456名居民进行基线调查。结果显示35岁以上人群冠心病患病率为1．79％,标化患病率为1．45％。非条件Logistic回归分析表明,人均收入高、高血压病史、家族史、食把肉习惯、睡眠少、肥胖是我市居民患冠心病的危险因素。表明应针对危险因素,开展综合防治。     

Toxic effects of nine polycyclic aromatic compounds on Enchytraeus crypticus in artificial soil in relation to their properties

The aim of this study was to compare the toxic effects of selected two- and three-ringed PAHs (naphthalene, phenanthrene, and anthracene) and their N-heterocyclic analogs with one (quinoline, acridine, and phenanthridine) or two (quinoxaline, phenazine, and 1,10-phenanthroline) nitrogen atoms on the survival and reproduction of Enchytraeus crypticus in artificial soil. Toxicity of compounds was recalculated to soil pore-water concentrations using the data of chemical analyses of 0.01 M CaCl₂ extracts of spiked soils. When toxicity was based on molar concentrations in pore water (μmol/L), it significantly increased with increasing K_ow value. This relationship indicates nonpolar narcosis as the general toxicity mechanism of the tested compounds. In addition, significant correlation between the toxicity of PACs and their ionization potential has been identified by multidimensional QSAR models.