Springer Science and Business Media LLC

Các thử nghiệm thực địa đã được tiến hành để nghiên cứu sự phân hủy và mức độ dư lượng của bifenthrin trong lúa mì. Sau khi chiết xuất bằng acetonitrile, các mẫu được làm sạch bằng phương pháp chiết xuất pha rắn phân tán và được phát hiện bằng sắc ký khí – khối phổ. Thời gian bán hủy của bifenthrin trong mầm lúa mì dao động từ 2,4 đến 10,5 ngày. Tại thời điểm thu hoạch, dư lượng cuối cùng của bifenthrin dưới mức giới hạn dư lượng tối đa (0,5 mg/kg) do Ủy ban Codex Alimentarius hoặc Liên minh Châu Âu quy định trong hạt lúa mì, cho thấy rằng việc sử dụng loại thuốc trừ sâu này là an toàn cho con người. Tuy nhiên, mức độ dư lượng tương đối cao của bifenthrin trong rơm lúa mì cần được chú ý.

The Yangtze River drainage basins are China’s most important economic development zones and also the locations of several large-scale fluorine chemical industries. In order to reveal the contribution from the tributaries at the dividing point between the middle and lower reaches of the Yangtze River with respect to perfluorinated substances (PFASs), 17 PFAS compounds in surface water, groundwater, and tap water samples were analyzed in the tributary system of the Jiujiang section of the Yangtze River. The total concentrations of PFASs in the surface waters ranged from 7.8 to 586.2 ng/L. High proportion of short-chain compound PFBS in surface waters in Nanchang City, Poyang Lake, and the Yangtze River was observed which is likely of WWTPs’ origin.

An LD50 study of inhaled pentachlorophenol has been conducted. Seven groups of rats, consisting of 12 animals each, were exposed to the aerosol of sodium pentachlorophenate. The LD50 was 11.7 mg/kg body weight as shown on a probit curve.

Feasibility study carried out at the site prior to the full scale study showed that the introduced bacterial consortium effectively adapted to the local environment of the soil at bioremediation site. The soil samples were collected from the contaminated fields after treatment with bacterial consortium at different time intervals and analyzed by gas chromatography after extraction with hexane and toluene. At time zero (just before initiation of bioremediation), the concentration of total petroleum hydrocarbons in the soil (25-cm horizon) of plot A, B, C and D was 30.90 %, 18.80 %, 25.90 % and 29.90 % respectively, after 360 days of treatment with microbial consortia was reduced to 0.97 %, 1.0 %, 1.0 %, and 1.1 % respectively. Whereas, only 5 % degradation was observed in the control plot after 365 days (microbial consortium not applied).