Occurrence, effects, detection, and photodegradation of triclosan and triclocarban in the environment: a review

Antibacterial agents like triclosan (TCS, 5-chloro-2-(2,4-dichlorophenoxy)phenol) and triclocarban (TCC, 3-(4-chlorophenyl)-1-(3,4-dichlorophenyl)urea are commonly found in everyday household and personal care products. Both compounds are widely distributed in the environment, acting as potential sources of contamination to ecological safety and human health problems such as algal growth-inhibiting effects; bioaccumulation in algae; endocrine-disrupting effects; development of microbial resistance, and formation of toxic degradable products. Environmentalists are increasingly concerned about the emergence of these micro-organic pollutants in the environment. This review paper focuses on the current state of knowledge, occurrence, effects, detection, and removal techniques for triclosan and triclocarban in the environment. People are exposed to these antibacterial agents when transported from wastewater treatment plants, air, dust, household products, and personal care products. These exposures lead to bioaccumulation in human tissue and biomagnification in the food chain. Surveys have revealed that TCC and TCS under sunlight formed toxic and persistent constituents like chlorinated phenols, methyl triclosan (MTCS), and biphenyl ethers. Different analytical approaches have been used to detect and degrade these compounds to ensure their complete removal in the environment but are found inadequate to effectively eliminate TCS and TCC. Advanced oxidation processes (AOPs) have shown to be promising in successfully breaking down TCS and TCC, considering material and energy consumption and emission of carbon (IV) oxide. Therefore, robust strategies such as electrochemical and nanomaterial methods should be implemented to determine and sequester TCS and TCC in the environment. Furthermore, regulatory bodies and environmental experts should be concerned about the fate and nanocatalyst photodegradation of triclosan and triclocarban in the environment.