三卤甲烷（THM）前体的表征及其最终从水中去除是一个难以捉摸的目标。存在相互矛盾和高度可变的结果。通过对马萨诸塞州三个具有不同地理和地貌性质的地区的腐殖物质进行采样，研究了THMs的前体。对土壤和水中的黄腐酸组分进行碳分析，然后氯化生成三卤甲烷。微波发射检测表明，不同来源的THM生成量差异不大，但发现低分子量组分和高分子量组分之间存在差异。密度更高的氯仿馏分往往含有更多的碳，这表明它们的去除将实现最大的THM减少。 包括14个参考文献、表格和图表。

The characterization of trihalomethane (THM) precursors and their eventual removal from water are elusive goals. Conflicting and highly variable results exist. Precursors of THMs were examined by sampling humic substances from three regions in Massachusetts with dissimilar geographic and geomorphic natures. Fulvic acid fractions from soil and water were analyzed for carbon and then chlorinated to produce THMs. Microwave emission detection showed little variation in THM production between sources but revealed differences between low and high molecular weight fractions. More dense chloroform fractions tended to contain greater amounts of carbon, suggesting that their removal will achieve the greatest THM reduction. Includes 14 references, tables, figures.