2-naphthylamine toxicity

Abstract

In the past, 2-naphthylamine (2-NA) was used for the production of azo dyes, as an antioxidant in the cable industry and in the rubber industry. Despite the fact that 2-NA is not produced on an industrial scale, it is still used in small quantities as a model bladder carcinogen in laboratories, and also for sewage control, water analysis and oxytocinase assays. In addition, it is detected in the air in coke ovens, where it is formed as one of the pyrolysis products. The main aim of this work is to provide an actual literature review for health risk assessments related to 2-NA which is still used in laboratories. Occupational exposure to 2-NA is important for the respiratory tract, mucous membranes and the skin, and, to a lesser extent, for absorption from the gastrointestinal tract. It is absorbed into the body through the skin and by inhalation, and then undergoes metabolic changes. Most of the absorbed 2-NA dose is excreted in the urine, in the form of metabolites, metabolites conjugated to acids, and even in an unchanged form. Based on literature data, the effects of 2-NA toxicity in sub-chronic and chronic exposure include contact dermatitis, chronic cystitis and bladder cancer. The authors have concluded that it is recommended to determine the occupational exposure limit which will allow preparing the exposure assessment of people at work.

The Male Reproductive Toxicity Caused by 2-Naphthylamine Was Related to Testicular Immunity Disorders

“…The lethal doses 50 (LD50) of NAP to rats was indicated by experimental studies at 727 mg/kg. The carcinogenicity of NAP was investigated through distinct exposure routes, including oral administration, subcutaneous injections, and intraperitoneal injections [2]. Thus, the intragastric administration of NAP is an effective approach for animal poisoning.…”

“…2-naphthylamine (NAP), containing two fused aromatic rings, is referred to as a kind of polycyclic aromatic hydrocarbon (PAH) [1]. Occupational exposure to 2-naphthylamine (NAP) primarily takes place in the laboratories employing NAP for cancer research; the workers are exposed to NAP from fumes after pyrolysis and from the metabolic process of nitric polycyclic aromatic hydrocarbons in dye and rubber industrial production [2]. Notably, recent research found that cigarettes, including e-cigarette smoke, and the fumes from heating food oils, are the main sources of general population exposure [3].…”

“…The absorption of NAP occurs through the skin, mucous membranes, inhalation, and gastrointestinal tract, and NAP in the body is mainly excreted in the urine after metabolism or in initial conditions and shows genotoxicity by forming DNA adducts in the bladder and liver [2]. People were subjected to dysuria, painful urination, and blood urine, as well as chronic contact dermatitis after exposure to NAP for the sensitization test [5].…”

A new method for the determination of naphatylamines in workplace air for occupational exposure assessment

“…jako substancja modelowa w badaniach nad rakiem. Do narażenia na 2-NA może dojść podczas pirolizy związków organicznych zawierających azot, a także podczas ogrzewania olejów spożywczych i poprzez narażenie na dym tytoniowy [14,15].…”

“…Według Centralnego Rejestru Danych o Narażeniu na Substancje, Mieszaniny, Czynniki i Procesy Technologiczne o Działaniu Rakotwórczym lub Mutagennym w Polsce w 2017 r. na działanie 2-NA i jej soli było narażonych 208 osób (201 na 2-NA i 7 na jej sole). Osoby narażone pracowały w laboratoriach uczelnianych, instytutach, inspekcjach, urzędach kontrolnych, laboratoriach zakładów farmaceutycznych i w zakładzie produkującym farby [15,17].…”