Resins, drinking water

Certain resins shown to be more Clays shown to be ineffective effective than G AC in removing in removing most tastes and low M.W. organics. such as THM s odors from drinking water Resins ... 

Groundwater is vulnerable to pollution by chemicals carried by rainwater, leaching from waste sites or from waste water carrying industrial or agricultural effluent. Treatment of drinking water may remove some, but not all, of these contaminants. Some polycarbonate or metal water pipes that are lined with epoxy resin lacquers may release bisphenol A. 

Le Bel GL, Williams DT, Griffith G, et al. 1979. Isolation and concentration of organophosphorus pesticides from drinking water at the ng/L level, using macroreticular resin. J AOAC 62 241-249. 

Drinking water Sample collection on XAD-2 resin solvent extraction solvent exchange GC/NPD confirmation by GC/MS Low ppt >70 LeBel et al. 1981... 

LeBel GL, Williams DT, Benoit FM. 1981. Gas chromatographic determination of tnalkyl/aryl phosphates in drinking water following isolation using macroreticular resin. J Assoc Off Anal Chem... 

Organic matter in unpolluted freshwater is usually in the form of humic acids (Section 13.6), which may discolor drinking water, foul ion-exchange resins, transport toxic metal ions, or generate carcinogenic chlorocarbons if the water is chlorinated (see below). Humic compounds may be removed by coagulation. Low levels of organic solutes can be removed by sorption on activated charcoal. 

Caprolactam may be released to the environment during its manufacture and use in the preparation of resins and plastics (United States National Library of Medicine, 1997). It has been detected in surface water, groundwater and drinking-water (lARC, 1986). 

Mean recoveries are for triplicate determinations from drinking water, spiked at 0.5-5 ppb (nominally 1 ppb), using XAD-4 resin sorbent columns. 

Use of Large-Volume Resin Cartridges for the Determination of Organic Contaminants in Drinking Water Derived from the Great Lakes... 

Macroreticular resins, particularly the Amberlite XAD series, have been used extensively to isolate and concentrate trace organic compounds from drinking water (1-8). We have previously reported the use of an XAD cartridge for this purpose and have evaluated the system for the analysis of organophosphorus pesticides (OPs) (4), polynuclear aromatic hydrocarbons (PAHs) (5), phosphate triesters (TAAPs) (6), or-... 

It is uncertain just how relevant the results for these resin studies are to actual drinking waters because lead in drinking water is likely to be in solution and to have had time to reach equilibrium. Tests on actual drinking waters with background levels of lead will provide more definite answers to these questions. 

Results of lead studies indicate that dissolved lead at 25 ppb is not isolated by the XAD-4 quaternary resin. However, if lead is precipitated in the drinking water sample, the resin acts as a filter, and the precipitated lead compounds collected on the resin can be dissolved by the acid/methanol eluant. Experiments with the presence of humic substances and lead were conducted because humic substances can act as chelating agents for heavy metals. Approximately 85 of the lead was recovered, but lead was removed from water because of the initial precipitation of this element. This phenomenon may not occur in actual field sampling because all lead compounds should be in a dissolved form. 

Figure 1. Effect of resin type on the mutagenic activity of drinking water concentrates in the Ames test. The sampling, 7000-fold concentration with either XAD-2 or XAD-4/8, DMSO elution (20 mL, neutral fraction), and subsequent mutagenicity testing were as described in Materials and Methods. Similar concentrates of The Hague tap water were used as controls. Each point represents the average of four plates, and 0.50 mL of concentrate corresponds to 3.5 L of water per plate.

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