4,4'-Dibrombiphenyl

This chemical does not meet GHS hazard criteria for 3.8% (2 of 53) of reports.

Danger

H302 (88.7%): Harmful if swallowed [Warning Acute toxicity, oral]

P203, P261, P264, P264+P265, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P305+P354+P338, P317, P318, P319, P321, P330, P332+P317, P362+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 53 reports by companies from 9 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

S - indicates a substance that is identified in a final Significant New Use Rule.

Restricted substance: 4,4'-dibromobiphenyl

PBBs can be absorbed via oral, inhalation, and dermal routes. Due to their lipophilic nature, PBBs, especially the highly brominated congeners, tend to accumulate in lipid-rich tissues such as the liver, adipose, skin, and breast milk. Certain PBB compounds are metabolized by the microsomal monooxygenase system catalyzed by cytochrome P-450 of the type induced by phenobarbital. The rate of metabolism may depends on the bromine substitution pattern. PBB congeners of low bromine content are transformed into hydroxylated derivatives that are predominately eliminated in the urine. Highly brominated congeners are either retained or excreted unchanged in the feces. (L628)

PBBs can be used as flame retardants and may be added to the plastics used to make products like computer monitors, televisions, textiles, and plastic foams to make them difficult to burn. However, the use of PBBs is banned or restricted in most areas due to their toxicity and persistence in the environment. (L628, L629)