Rader J I, Peeler J T, Mahaffey K R
Environ Health Perspect. 1981 Dec;42:187-95. doi: 10.1289/ehp.8142187.
The relative toxicity of low doses of lead acetate provided steadily in drinking water or by mouth once per week was studied in weanling and adult rats. Free erythrocyte protoporphyrin and urinary delta-aminolevulinic acid levels were measured, as well as lead levels in blood and kidney. The accumulation of lead in brain tissue and in bone (femur) was measured to determine the effect of age and schedule of administration on tissue distribution and retention of lead. Total intakes of lead during the 60-week experimental period were: weanling and adult rats exposed to drinking water supplemented with 200 microgram of lead acetate/ml: 127 +/- 10 mg and 160 +/- 16 mg, respectively; weanling and adult rats dosed with lead acetate orally once per week: 132 mg and 161 mg, respectively. Increased toxic effects of lead in the weanling animals were apparent in most of the parameters measured (urinary delta-aminolevulinic acid and blood, brain, femur and kidney lead levels). This pattern was observed in weanling rats exposed to lead steadily through drinking water or dosed orally with an equivalent quantity of lead once per week. Lead levels in blood were highly correlated with the accumulation of lead in brain, femur, and kidney tissue in both groups of weanling rats. In adult rats, significant correlations between blood lead and kidney lead and between blood lead and femur lead were found only in the rats receiving lead steadily in drinking water.
研究了低剂量醋酸铅通过每周一次经口给药或持续添加于饮用水中，对断奶大鼠和成年大鼠产生的相对毒性。测量了游离红细胞原卟啉和尿δ-氨基乙酰丙酸水平，以及血液和肾脏中的铅含量。测量了脑组织和骨骼（股骨）中的铅蓄积情况，以确定年龄和给药方案对铅在组织中的分布和潴留的影响。在为期60周的实验期内，铅的总摄入量分别为：饮用添加200微克/毫升醋酸铅的水的断奶大鼠和成年大鼠，分别为127±10毫克和160±16毫克；每周经口给予醋酸铅一次的断奶大鼠和成年大鼠，分别为132毫克和161毫克。在大多数测量参数（尿δ-氨基乙酰丙酸以及血液、脑、股骨和肾脏中的铅含量）中，铅对断奶动物的毒性作用增强是明显的。在通过饮用水持续接触铅或每周经口给予等量铅的断奶大鼠中均观察到这种模式。两组断奶大鼠血液中的铅含量与脑、股骨和肾脏组织中的铅蓄积高度相关。在成年大鼠中，仅在饮用含铅水的大鼠中发现血铅与肾铅以及血铅与股骨铅之间存在显著相关性。
