Cholinesterase-inhibiting Potentials of Amberlite XAD-2 Resin Extracts Collected from River and Drinking Waters in Northwest District of Chiba Prefecture, Japan

Abstract

Amberlite XAD-2 resin extracts of river and drinking water sampled in each month during the period from January to December 2008 from the Northwest district of Chiba Prefecture were investigated to characterize and determine their cholinesterase (ChE)-inhibiting potentials and pesticide levels. The XAD-2 extracts from river water collected during the mid-spring to mid-summer periods exhibited strong inhibition effect to horse serum ChE, reflecting the application of organophosphorus and carbamate pesticides to paddy fields. Gas chromatographicmass spectrometric (GC/MS) determinations of the XAD-2 extracts of the river water collected during spring to summer periods also showed to be comparatively high levels of agricultural chemicals, such as herbicides, insecticides and fungicides, as compared with those detected in the drinking water. Although a considerable reduction in the ChE-inhibiting potentials and in the GC/MS detectable compound levels was observed for the river water samples, it is particularly interest that ChE-inhibiting potentials still remained in the drinking water.

Effect of hypochlorite oxidation on cholinesterase-inhibition assay of acetonitrile extracts from fruits and vegetables for monitoring traces of organophosphate pesticides

“…A sample volume of 1 μl was splitlessly injected into the GC-MS at 270°C. The confirmation and determination of organophosphorus and carbamate pesticides tested in the present study were carried out according to the methods described in previous papers (Kawakami et al, 2008;Kanno et al, 2010Kanno et al, , 2012.…”

“…In order to provide greater insight into the possible role of organic compounds in the formation of chlorinesubstituted or chlorine-oxidised compounds and chlorineinduced mutagens, our laboratory has further explored the study of the aqueous chlorination chemistry of organic compounds (Onodera, 2010;Kanno et al, 2010Kanno et al, , 2012. In the present study, we studied the chlorination conditions of the anti-cholinesterase inhibitors, organophosphothionate and carbamate pesticides in the acetonitrile extracts of fruits and vegetables, and developed a combination method of hypochlorite oxidation and ChE-inhibiting assays to monitor traces of these contaminants in apple, tomato, cucumber and strawberry.…”

Enhancement of anti-cholinesterase activity of aqueous samples by hypochlorite oxidation for monitoring traces of organophosphorus pesticides in water

“…River water sample (20 l) as source water was collected from the Nodabashi of the Edo River on June 18 th 2008 (Kanno et al, 2010). This river is typically to the Kamihanawa purification plant and then distributed to the Northwest district of Chiba Prefecture, including to our laboratory.…”

“…37 No. 2 and drinking water concentrates (XAD-2-resin adsorption and n-hexane/acetone extraction) were prepared according to the procedure described in previous paper (Kanno et al, 2010).…”

“…In order to provide further insight into the possible role of organic compounds in the formation of chlorine-substituted compounds and chlorine-induced mutagens, our laboratory has continued the study of the aqueous chlorination chemistry of organic compounds (Kanno et al, 2010;Onodera, 2010). In the present study, the fate of the anticholinesterase inhibitors, organophosphorus and carbamate pesticides, in chlorinated water was studied in more detail and a combination method of hypochlorite oxidation and ChE-inhibiting assays was developed for monitoring these contaminants in natural and drinking waters.…”