ABSTRACT
Objective To understand and improve the laboratory detection capacity of water manganese in testing organizations of Shaanxi Province． Methods The self-made manganese capacity testing samples were used as the reference in this proficiency testing program. The homogeneity of the samples was tested by single factor analysis of variance. The t-test method was used to evaluate the stability of the samples. The results of manganese in water provided by participant laboratories were analyzed by the robust statistical technique Z-score. Results A total of 136 laboratories participated in the proficiency testing program throughout the province. Among them, 129 laboratories (including retest laboratory) or 94.85% of total participating laboratories obtained satisfactory results. Conclusion The water quality monitoring agencies of our province had shown a strong detection capability for the determination of metal elements in drinking water, which ensures to provide safe water supply to the residents in Shaanxi Province.
ABSTRACT
To establish a spectrophotometric method for detecting selenium in drinking water,some subjects,such as the features of absorption spectrum of the reacting product of selenium and diaminonaphthalene,disturbance of other coexisting ions,detection range,detection limit,precision and accuracy were studied.The results showed that:the maximum absorption wavelength of the reacting product of Se4+and 2,3-diaminonaphthalene was 377 nm,the detection limit,molar absorptivity (ε377) and linear range of this method was 0.018 μg/50 ml,2.7×104 L/(mol·cm)and 0.2～10 μg/50ml respectively.The regressive equation was A＝0.077C＋0.014 with a correlation coefficient r value of 0.9999.The relative standard deviation (RSD) and recovery rate were ＜54.7% and 96.5%～106% respectively.This method was simple,sensitive and accurate,could meet the requirement of the routine monitoring of selenium in drinking water.
ABSTRACT
Objective To explore the method for simultaneous determination of arsenic and mercury in drinking water. Methods Atomic fluorescence spectrometry was applied for simultaneous determination of arsenic and mercury in drinking water. The best working conditions of the determination, such as the height of flame of atomizer, current of hollow cathode lamp, reducer, acidity and required amount of NaBH 4 were defined in this assay. Results The determination range of arsenic, the correlation coefficient and detection limit for arsenic were 0～40 ng/ml,0 999 5 and 0 10 ng/ml respectively, and were 0～80 ng/ml, 0 999 3 and 0 02 ng/ml for mercury respectively. The precisions and recovery rates of the simultaneous determination of arsenic and mercury in drinking water were 0 94%～5 61% and 94%～110%. Conclusion This method with advantages such as simple, rapid, sensitive, high accuracy and less interference, was suitable for simultaneous determination of arsenic and mercury in drinking water.
ABSTRACT
Environmental arsenic content is influenced by natural condition, microorganism and human activity.Certain natural conditions favor arsenic mobilization to the environment.Some microorganisms adapt in high arsenic environment, which is an important factor for arsenic biotransformation and mobilization in the environment.Moreover, human activities can intensify arsenic accumulation in the environment.The environmental arsenic accumulates rapidly through the food chain and enters human bodies to be detoxicated through methylation.Water arsenic pollution is one of very serious public health problems, which not only causes acute and chronic toxicosis, but also increases human susceptivity to many kinds of diseases.