Studies on the acute toxicity of fluoride ion to stickleback,fathead minnow,and rainbow trout

We have studied the acute toxicity of fluoride ion to $\text{Gasterosteus aculeatus}$, $\text{Pimephales promelas}$, and juvenile $\text{Salmo gairdneri}$. LC50 values varied with species and (due to precipitation) initial water hardness. Exposure to elevated fluoride levels in water resulted in increased blood fluoride levels in $\text{Salmo gairdneri}$.     

富伦纸业污染治理成果的启示

本文报道了富伦纸业通过工艺与设备的调整与改造，工艺全程控制与末端综合治理，不但治理了环境污染，还获得了一定的经济效益。     

煅烧对粉煤灰合成4A沸石的作用

研究了煅烧对粉煤灰合成4A沸石除炭(有机物)增白和活化的两个作用,试验确定了粉煤灰最佳的锻烧条件:温度为850℃,时间为2h。在此条件下煅烧,通过XRD、SEM分折和白度测定,结果显示:破坏了粉煤灰中的晶相结构和溶解了玻璃体,白度达到了63。     

Epidemiological investigation on mercury contamination in gold mining and its effect on health

Ｉｎｒｅｃｅｎｔｙｅａｒｓ,ｍｅｒｃｕｒｙｃｏｎｔａｍｉｎａｔｉｏｎｈａｓｂｅｅｎ ｐａｉｄ ｇｒｅａｔａｔｔｅｎｔｉｏｎｔｏｏｖｅｒｔｈｅｗｏｒｌｄ(Ｚｉｌｌｏｕｘ ,1993;Ｍｏｎａｍｙ ,1993;Ｇｕａｎ ,1994;Ｙａｎｇ ,1992 ;Ｌｉ,1993;1994;ＳＣＯＰＥ ,1994) .ＴｈｅｐｒｉｎｃｉｐａｌｆｏｃｕｓｉｓｔｏｄｅｃｒｅａｓｅＨｇｃｏｎｔａｍｉｎａｔｉｏｎｉｎｏｒｄｅｒｔｏｐｒｏｔｅｃｔｔｈｅｅｃｏｓｙｓｔｅｍｅｎｖｉｒｏｎｍｅｎｔａｎｄｔｈｅｈｕｍａｎ’ｓｈｅａｌｔｈ .Ｉｔｉｓｄｉｆｆｅｒｅｎｔｆｒｏｍ“ｍｉ…     

上海地铁车站空气中CO2浓度调查

１９９８年５月末对上海地铁人民广场站和漕宝路站２个站台内空气中ＣＯ２浓度进行了监测，以日本，美国，澳大利亚和韩国４个国家的室内空气质量标准进行影响评价。结果表明：２个地铁站内空气中ＣＯ２浓度在大部分运营时间内低于１５７１．４或１１７８．８ｍｇ／ｍ＾３，属“可”或“良”。     

Echocardiographic diagnosis of fetal marfan syndrome at 34 weeks' gestation

Fetal echocardiography was performed during the third trimester in a normal primigravida. The fetal heart was severely affected with the typical cardiac manifestations of Marfan syndrome. The medical history of the father was investigated and a mild form of the syndrome was diagnosed. The neonate died at 2 months of age of congestive heart failure.     

Effect of cholinergic antagonists on the bradycardic response of limpets to copper

The effect of cholinergic antagonists on the bradycardia induced by waterborne copper in the Mediterranean limpet Patella caerulea was investigated by using non-invasive recording of cardiac activity of whole animals. Preliminary tests were conducted to check the role of cholinergic and serotoninergic systems in the control of heart rate of P. caerulea. Superfusing the whole limpets with carbachol (cholinergic agonist) at 5×10^–5 M produced a negative inotropic and chronotropic effect (bradycardia), while superfusion with 5-hydroxytryptamine produced a positive inotropic and chronotropic effect (tachycardia). Exposure of limpets to a solution of copper in artificial seawater (0.25 mg l^–1, 3 h) reduced their heart rate to about 80% the value recorded in copper-free water. This bradycardia was inhibited by injecting the limpets with atropine (cholinergic muscarinic antagonist) at 21 g g^–1 wet flesh weight and with benzoquinonium [cholinergic nicotinic antagonist blocking the K⁺ mediated acetylcholine (ACh) response] at 10 and 100 g g^–1 prior to copper exposure. In contrast, D-tubocurarine (cholinergic nicotinic antagonist blocking Na⁺ mediated ACh response) had no effect at 85 g g^–1. These results agree with the involvement of the cholinergic system in the bradycardic response of limpets to copper, and support the view that gastropod ACh receptors do not fit the vertebrate nicotinic–muscarinic classification.Communicated by R. Cattaneo-Vietti, Genova     

Monitoring of copper,arsenic and antimony levels in agricultural soils impacted and non-impacted by mining activities,from three regions in Chile

This paper reports a comparative study of the concentration of three important environmental elements that are often found together in mineral deposits and then associated with mining activities; copper, arsenic and antimony. These elements were determined in 26 different agricultural soils from regions I, II and V in Chile, zones where the most important and biggest copper industries of this country are located. As background levels of these elements in soils have not been well established, in this study, both, impacted and non-impacted agricultural soils from different regions were considered. The relationships between the concentrations of these elements in soils were also examined. The concentration ranges for copper, arsenic and antimony were 11-530; 2.7-202 and 0.42-11 mg kg(-1) respectively. The copper concentrations in non-polluted soils from the north and central zone of Chile were similar. However, three sites from the north region have copper concentration as higher as 100 mg kg(-1), values that exceed the critical concentration for copper in soils. The concentration of arsenic and antimony in the north soils were higher than in non-impacted ones and, in the case of arsenic, greatly exceeded the world average concentration reported for this element in soils. The highest arsenic and antimony concentrations were found in Calama and Quillagua soils, two different sites in the Loa valley. The arsenic/antimony concentration ratio was higher in Quillagua soil. The high concentrations of three elements determined in impacted soils from region V (Puchuncaví and Catemu valleys) clearly shows the impact produced in this zone by the industrial and mining activities developed in their proximities. At Puchuncaví valley a clear decrease was observed in copper, arsenic and antimony concentrations in soils on the function of the distance from the industrial complex "Las Ventanas", and all concentrations exceeded the reported critical values for this matrix. Instead at Catemu valley, only the copper concentration was higher than this value. Statistically significant correlation was found for Cu-Sb in all soils; more significant Cu-As, Cu-Sb and Sb-As correlations were evaluated for soils from Puchuncaví and Catemu valleys, corroborating that high concentrations of copper, arsenic and antimony in these soils coming from the same pollution sources, the copper industry and the thermoelectric power plant.     

Laboratory study of the emission of NO and N2O from some Belgian soils

The NO, NO₂ and N₂O emission was measured, upon application of nitrate, ammonium and both, to four Belgian soils with different characteristics. The addition of NH ₄ ⁺ caused higher NO and N₂O emissions than the addition of no nitrogen, or the addition of NO ₃ ^– . In contrast to the two soils with a pH of approximately 8 the two soils with a pH around 6 showed a considerable delay in production of both NO and N₂O upon the application of the ammonium, probably due to the lag-period of nitrification. The soils with a pH of 8 gave higher emissions on the application of NH ₄ ⁺ than the soils with a pH of 6. The emission of NO₂ was found to be considerably lower than the NO emission from the soils. The NO/NO₂ ratio varied between 5–25 at considerable NO emissions (>50 nmol kg^–1). In the controls of soil 1 and soil 2, which showed very low NO emissions ratios of <1 were observed. The N₂O/NO ratios varied between 5–20 when NO emissions were considerable (>50 nmol kg^–1). Soil 3 and 4 gave lower N₂O/NO ratios than soil 1 and 2. In the controls of soil 1 and soil 2, at low NO emissions, N₂O/NO ratios of >300 were observed. Soil 3 and 4 gave higher NO/NO₂ and lower N₂O/NO ratios than soil 1 and 2.     

Efficiency of a standardized artificial substrate for biological monitoring of river water quality

Before using macroinvertebrates in water quality assessment in the Chusovaya River (Russia, the Urals, 50°55N, 60° E), preliminary results of three sampling methods were compared: handnet, circular shovel and a standardized artificial substrate sampler. The artificial substrate consisted of glass marbles ( 20 mm). To compare the efficiency of these sampling methods the total numbers of taxa found at each location per sampling data were considered to be 100%. The highest efficiency was reached with the artificial substrate sampler. 75–100% of the taxa at the different locations were collected with this sampler. Only 5–19% and 10–20% of the taxa at each location per sampling date were collected with the circular shovel in the sand and gravel substrate respectively, being the lowest efficiency. Intermediate results were obtained with the hand net. 23–38% of the taxa were collected with this net. Based on these results and requirements placed upon sampling methods in general, the standardized artificial substrate sampler has been considered to be an optimal sampling device for macroinvertebrates in biological monitoring.