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毒物

任何会损害活组织、致伤或致死的物质(自然物或合成物)。由活的生物机体自然产生的毒物通常被称为毒素,若由动物产生则称为动物毒液。毒物可能是被咽下、吸入或由皮肤吸收。毒物不一定具有全或无效应;一些毒物的毒性比另一些毒物要大得多,如0.25克氰化钾就足以致命,而一次服用大量的精制食盐也会致命。毒性可以是急性的(摄入一剂之後立刻出现症状)或者慢性的(反覆或持续摄入毒物後最终出现症状,摄入化学性的致癌物质就是这样)。中毒反应可以是局部的(麻疹、水泡、发炎)或全身的(全身出血、抽搐、呕吐、腹泻、感觉模糊、麻痹、呼吸或心跳停止)。农业上的杀虫剂通常对人类是有毒的。一些工业用化学品具有高度毒性或是致癌物质。大多数药剂和保健品在不恰当服用或超量服用情况下都是毒物。大多数形式的放射线也是有毒的(参阅radiation injury)。亦请参阅antidote、arsenic poisoning、fish poisoning、food poisoning、lead poisoning、medicinal poisoning、mercury poisoning、mushroom poisoning。

poison

Any substance (natural or synthetic) that damages living tissues and injures or kills. Poisons spontaneously produced by living organisms are often called toxins, or venoms if produced by animals. Poisons may be ingested, inhaled, injected, or absorbed through the skin. They do not always have an all-or-none effect; some are far more toxic than others (e.g., 0.25 g of potassium cyanide may kill, whereas a massive single dose of table salt can kill). Poisoning may be acute (a single dose does significant damage) or chronic (repeated or continuous doses produce an eventual effect, as with chemical carcinogens). The effects produced by poisons may be local (hives, blisters, inflammation) or systemic (hemorrhage, convulsions, vomiting, diarrhea, clouding of the senses, paralysis, respiratory or cardiac arrest). Agricultural pesticides are often poisonous to humans. Some industrial chemicals can be very toxic or carcinogenic. Most drugs and health-care products can be poisons if taken inappropriately or in excess. Most forms of radiation can be toxic (see radiation injury). See also antidote, arsenic poisoning, fish poisoning, food poisoning, lead poisoning, medicinal poisoning, mercury poisoning, mushroom poisoning.