On November 28, the National Health Commission of the People's Republic of China (NHC) released a notice to amend GBZ 2.1-2019 Occupational Exposure Limits for Hazardous Agents in the Workplace Part 1: Chemical Hazardous Agents. The amendment takes effect the same day it was released.
GBZ 2.1-2019 is a national standard that stipulates hygiene requirements, testing evaluation and control principles of occupational exposure to hazardous agents in the workplace. It set out occupational exposure limits (OELs) for 358 hazardous chemicals (Table 1), 49 kinds of dust (Table 2) and 3 biological agents (Table 3), and biological exposure limits (BELs) for 28 hazardous chemicals (Table 4).
Compared with GBZ 2.1-2019, the amendment revises OELs and critical adverse health effects for Benzene in Table 1 (highlighted in yellow) as:
|No.||Chemical name||CAS number||OELs (mg/m3)||Critical adverse health effects||Remark|
Neurological damage, hematological toxicity
1. Chemical substance with the remark of “skin” is likely to be absorbed by humans through skin exposure.
2. International Agency for Research on Cancer (IARC) classifies chemicals that are definitely carcinogenic to humans as Group 1 (G1).
In addition, one chemical substance is added into Table 4:
|No.||Chemical name||Biological monitoring indicators||BELs||Sampling time|
|29||Trimethyltin chloride (TMT)|
Trimethyltin chloride urine
|500 µg/g Cr||No strict requirement|
|Trimethyltin chloride in blood|
|No strict requirement|