| environ. |
persistence The capacity of a substance to remain chemically stable. This is an important factor in estimating the environmental effects of substances discharged into the environment. Certain toxic substances (e.g., cyanides) have a low persistence, whereas other less immediately toxic substances (e.g., many organochlorines) have a high persistence and may therefore produce more serious effects (物质的一种能力，保持化学稳定性。这种物质是影响环境评估的一个重要因素。某些有毒物质(如氰化物)有较弱的持久性，而其它不是立即有毒的物质(如很多有机氯)有很强的持久性，并可能因此产生更严重的影响。) |
