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Neutron activation analysis (NAA) methods were employed for the determination of total arsenic, and water soluble As(III) and As(V) compounds in freshwater fish/shellfish and plant samples from Southern Thailand. Total arsenic concentrations varied from 0.05 to 425 mg kg. Water soluble arsenic species were separated by solvent extraction using ammonium pyrrolidinedithiocarbamate (APDC)/methylisobutylketone (MIBK) followed by NAA. The water soluble As(III) and As(V) levels varied from 0.07 to 26.4 and 0.03 to 22.9 mg kg, respectively. The As(III) and As(V) detection limits were 0.007 for fish/shellfish, 0.005 for As(III) and 0.006 mg kg for As(V) in plants. This separation method allows for the determination of water soluble As(III) and As(V) using commonly available and inexpensive laboratory equipment and chemicals, which can be coupled to a variety of quantification techniques. [ABSTRACT FROM AUTHOR]

Thailand is the number one global exporter and among the top five producers of rice in the world. A significant increase in anthropogenic contamination in agricultural soils over the past few decades has lead to concerns with cadmium and its uptake in rice. The cadmium levels in Thai rice from different sources/areas were determined and used to estimate the potential health risks to consumers. The cadmium concentration in the commercial rice samples ranged from below the detection limit to 0.016 mg/kg. The cadmium concentrations in the contaminated rice samples ranged from a low of 0.007 mg/kg to a high of 0.579 mg/kg. Five of the calculated values exceed the proposed PTWI, with one value almost three times higher and two values almost double. The three highly elevated values are certainly a concern from a health standpoint. Ultimately, action is required to address the health implications resulting from the cadmium contamination in agricultural soils used for rice production in a few select areas of Thailand. Overall, this study indicates that the vast majority of rice produced, consumed and exported by Thailand is safe pertaining to cadmium content. [ABSTRACT FROM AUTHOR]

A combination of solid phase extraction, coprecipitation, and neutron activation techniques has been used to develop a speciation analysis method based on green chemistry for the major arsenic species in drinking water. Arsenate as As(V), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) are separated and preconcentrated by strongly anion and cation exchange columns in tandem while As(III) remains in the effluent. These species are then selectively eluted and As(III) coprecipitated with bismuth sulphide. This simple method has been applied to the analysis of water reference materials with good results. The detection limits are 0.9, 1.7, 1.6, 3.8 and 16 ng mL−1 for As(III), As(V), MMA, DMA and total arsenic, respectively, using a neutron flux of 2.5 × 1011 cm−2 s−1 at the Dalhousie University SLOWPOKE-2 reactor (DUSR) facility and anti-coincidence gamma-ray spectrometry. [ABSTRACT FROM AUTHOR]

An instrumental neutron activation analysis (INAA) method was developed for the simultaneous determination of 19 elements in 10 individual food items from Ghana. The samples were irradiated for 1 minutes in a neutron flux of 2.5. [ABSTRACT FROM AUTHOR]

Reports on a study on the copper contamination and cadmium, silver, and zinc concentrations in the digestive glands of American lobster, Homarus Americanus, from the Inner Bay of Fundy, Atlantic Canada. Materials and methods used; Results on the metal analysis; Comparison between all the chemical elements over different sites of inner bays.

Tissues, eggs and bile of adult Atlantic cod raised in captivity and fed natural food with no additional halogenated compounds of any kind were analyzed by neutron activation. There was a large difference in the tissue distributions of extractable organic chlorine (EOCl) and bromine (EOBr). Liver lipid had the lowest levels of EOBr and EOCl, of all the components investigated, and eggs had the highest levels of EOCl. Heart contained the most EOBr and EOCl per unit lipid, of the tissues. The presence of a larger proportion of EOBr than EOCl in bile suggests a higher rate of excretion of EOBr. The EOCl concentratios found in cod egg lipids were about 5 times higher than the highest values previously reported for EOCl in lipid. [ABSTRACT FROM AUTHOR]