Bailey E, Brooks A G, Farmer P B, Street B
MRC Toxicology Unit, Carshalton, Surrey, UK.
Environ Health Perspect. 1993 Mar;99:175-7. doi: 10.1289/ehp.9399175.
4,4'-Methylene-bis(2-chloroaniline) (MOCA) is widely used as a curing agent in the plastics industry. The determination of the covalently bound reaction products to hemoglobin (Hb) has been investigated as a biomonitoring method for occupational exposure to this potential human carcinogen. Initial studies using the 14C-ring-labeled MOCA showed that 24 hr after a single IP dosage to rats (3.74 mumole/kg), 0.08% of the administered dose was adducted to the Hb, and base hydrolysis liberated 38% of the bound radioactivity. The only product released on hydrolysis was the parent diamine. A specific and sensitive assay procedure using capillary gas chromatography-mass spectrometry has been developed for determining the base-released MOCA adduct down to levels of 20 pmole/g Hb. This method has been used to establish a linear dose-response relationship in IP dosed rats between production of the adduct and dose of MOCA (3.74-44.94 mumole/kg). It is proposed to use analysis of the Hb adduct as a dosimeter for industrial workers exposed to MOCA.
4,4'-亚甲基双（2-氯苯胺）（MOCA）在塑料工业中广泛用作固化剂。作为职业接触这种潜在人类致癌物的生物监测方法，已经对其与血红蛋白（Hb）的共价结合反应产物的测定进行了研究。使用14C环标记的MOCA的初步研究表明，对大鼠单次腹腔注射剂量（3.74微摩尔/千克）24小时后，给药剂量的0.08%与Hb发生加合，碱水解释放出38%的结合放射性。水解时释放的唯一产物是母体二胺。已经开发出一种使用毛细管气相色谱-质谱法的特异性和灵敏的测定程序，用于测定碱释放的MOCA加合物，低至20皮摩尔/克Hb的水平。该方法已用于在腹腔注射给药的大鼠中建立加合物产生与MOCA剂量（3.74-44.94微摩尔/千克）之间的线性剂量反应关系。建议将Hb加合物分析用作接触MOCA的产业工人的剂量计。
