OBJECTIVETo establish a method for determining o-tolidine in workplace air by gas chromatography.

METHODSo-tolidine in workplace air was collected with a glass fiber filter, desorbed with methanol, and determined by gas chromatography-flame ionization detector.

RESULTSThe concentration of o-tolidine showed a linear relationship with peak area within 0.04∼9.00 µg/ml; the detection limit was 0.04 µg/ml; the minimum detectable concentration was 0.0002 mg/m(3) (calculated by 375 L air sample); the sampling efficiency was 93%∼100%; the elution efficiency was 94%∼96%; the relative standard deviation was 0.8-2.5%. Sample could be stored at 4 °C for at least 8 days and at room temperature for as long as 6 days.

CONCLUSIONThis determination method meets the requirements of Guide for establishing occupational heath standards-Part 4 Determination methods of air chemicals in workplace (GBZ/T 210.4-2008) and is suitable for determination of o-tolidine in workplace air.

Air ; analysis ; Air Pollutants, Occupational ; analysis ; Benzidines ; analysis ; Chromatography, Gas ; methods ; Workplace

Adult ; Aged ; Benzidines ; toxicity ; Coloring Agents ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Urinary Bladder Neoplasms ; epidemiology

OBJECTIVE: To assess the clinical features of children with developmental coordination disorder (DCD) and the effects of occupational therapy. METHOD: Seventeen children were diagnosed with DCD using by Bruininks-Osteretsky test of motor proficiency (BOTMP). To investigate the clinical features, neurological examinations such as soft neurological signs, speech evaluation, cognitive assessment, and psychiatric evaluation were performed on the 17 participants. Among the participants, 8 children had occupational therapy. BOTMP and cognitive function were evaluated both prior to and 6 months after the intervention. RESULTS: Children with DCD showed various soft neurological signs and co-morbidities such as attention-deficit hyperactivity disorder (ADHD), developmental language disorder, and emotional problems. The cognitive assessment revealed disproportionately low performance IQ for all subjects. After occupational therapy, scores for BOTMP and performance IQ increased significantly. CONCLUSION: The clinical features of DCD are heterogeneous and occupational therapy focused on motor proficiency was effective. This study supports raising interest in and attention on children with motor coordination difficulties.
Benzidines ; Child ; Humans ; Language Development Disorders ; Motor Skills Disorders ; Neurologic Examination ; Occupational Therapy

OBJECTIVETo investigate the effect of intracellular 5-lipoxygenase on oxidation of benzidine in HBE cells and to provide further evidence that lipoxygenase is an alternative pathway for the oxidation of xenobiotics mediated by cytochrome P450.

METHODSEnzyme system test: Soybean lipoxygenase (SLO), substrate (benzidine) and other components reacted in the enzyme system, followed by detection of the reaction products by spectrophotometry. In vitro test: After HBE cells were exposed to benzidine, the protein levels of 5-lipoxygenase in HBE cells were assessed by Western-blot, and the DNA damage by the single cell gel electrophoresis. At last, the effect of the specific inhibitor of 5-lipoxygenase (AA861) on 5-lipoxygenase protein expression and DNA damage in HBE cells were detected.

RESULTSSLO could catalyze the co-oxidation of benzidine to generate benzidine diimine in the presence of hydrogen peroxide. Under optimal condition, numax value of the oxidation of benzidine catalyzed by SLO was 1.42 nmol*min(-1) SLO, and the Km value of benzidine was 1.48 mmol/L. EGCG could inhibit the oxidation of benzidine by SLO. Benzidine could induce 5-lipoxygenase protein expression in HBE cells, but AA861 was invalid. Benzidine caused DNA damage in HBE cells, which could be significantly inhibited by AA861.

CONCLUSION5-LOX protein expression in HBE cells can be regulated by benzidine, which suggests that the co-oxidation of benzidine by 5-LOX could produce into electrophile that could covalently bind to DNA and induce DNA damage, which could be one of the mechanisms for carcinogenesis of BZD. 5-LOX inhibitor AA861 can inhibit this effect.

Arachidonate 5-Lipoxygenase ; metabolism ; Benzidines ; pharmacokinetics ; toxicity ; Cells, Cultured ; DNA Damage ; drug effects ; Epithelial Cells ; drug effects ; enzymology ; metabolism ; Humans

OBJECTIVES: This study explored the clinical differences in attention-deficit hyperactivity disorder (ADHD) patients with and without developmental coordination disorder (DCD). METHODS: Participants were 49 children and adolescents with ages between 6 and 18 years. These subjects were placed into 2 groups: ADHD without DCD (24) and ADHD with DCD (25). We used several evaluation tools on both groups: the Affective Disorders and Schizophrenia-Present and Lifetime Version- Korean Version (K-SADS-PL), Wechsler Intelligence Scale for Children-III (WISC-IIII), Child Behavior Check List (CBCL), Korean Personality Rating Scale for Children (K-PRC), and Bruininks-Osretsky Test of Motor (BOT-2). RESULTS: Patients with both ADHD and DCD had a lower performance intelligence quotient and more internal and external behavioral symptoms than patients with ADHD but not DCD. It is possible that patients with ADHD and motor coordination problems should be noticed earlier and given intensive treatment.
Adolescent ; Anxiety ; Behavioral Symptoms ; Benzidines ; Child ; Child Behavior ; Comorbidity ; Depression ; Humans ; Intelligence ; Mood Disorders ; Motor Skills Disorders

OBJECTIVES: This study explored the clinical differences in attention-deficit hyperactivity disorder (ADHD) patients with and without developmental coordination disorder (DCD). METHODS: Participants were 49 children and adolescents with ages between 6 and 18 years. These subjects were placed into 2 groups: ADHD without DCD (24) and ADHD with DCD (25). We used several evaluation tools on both groups: the Affective Disorders and Schizophrenia-Present and Lifetime Version- Korean Version (K-SADS-PL), Wechsler Intelligence Scale for Children-III (WISC-IIII), Child Behavior Check List (CBCL), Korean Personality Rating Scale for Children (K-PRC), and Bruininks-Osretsky Test of Motor (BOT-2). RESULTS: Patients with both ADHD and DCD had a lower performance intelligence quotient and more internal and external behavioral symptoms than patients with ADHD but not DCD. It is possible that patients with ADHD and motor coordination problems should be noticed earlier and given intensive treatment.
Adolescent ; Anxiety ; Behavioral Symptoms ; Benzidines ; Child ; Child Behavior ; Comorbidity ; Depression ; Humans ; Intelligence ; Mood Disorders ; Motor Skills Disorders

OBJECTIVETo study expression of mutant p53 protein in workers occupationally exposed to benzidine and bladder cancer patients.

METHODSMutant p53 protein in serum from the workers occupationally exposed to benzidine and bladder cancer patients were determined with Immuno-PCR, while exfoliated urothelial cells in the urine samples were classified with Papanicolau grading.

RESULTSPositive rate of mutant p53 protein increased with the exposed intensity index in workers occupationally exposed to benzidine. The positive rate of mutant p53 protein in bladder cancer patients (83.3%) was significantly higher than that in the group 1 of exposed intensity index. The average scanning integrals of PCR amplified band in the group of bladder cancer patients and group 2 of exposed intensity index were both higher than that in the group 1 significantly. Workers in the groups of different exposed intensity indices were further stratified according to Papanicolau grades. In the group 2 of exposed intensity index, the average scanning integrals of PCR amplified band in the stratum of Papanicolau grade II and III were significantly higher than that in the strata of Papanicolau grade I. And in the group 3 of exposed intensity index, the positive rate of mutant p53 protein in the strata of Papanicolau grade III was higher than that in the strata of Papanicolau grade I significantly.

CONCLUSIONThe increase of exposed intensity may not only result in the positive rate of mutant p53 protein, but also the quantity of mutant p53 protein in serum within the low range of benzidine exposure. Once the exposed intensity was beyond that spectrum, the positive rate of mutant p53 protein in serum and the average scanning integrals of PCR amplified band were no longer enhanced with the increase of exposed intensity. There was tight correlation between Papanicolau grade of exfoliated urothelial cells and the positive rate or the quantity of mutant p53 protein for the higher benzidine exposure intensity.

Adult ; Aged ; Aged, 80 and over ; Benzidines ; toxicity ; Female ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Tumor Suppressor Protein p53 ; metabolism ; Urinary Bladder Neoplasms ; metabolism ; Urothelium ; metabolism

OBJECTIVETo test the possibility that certain efficient substrates for lipoxygenase (LOX) produce shuttle oxidants that stimulate the generation of reactive oxygen species from other chemicals.

METHODSMetabolic interactions were conducted in vitro between chlorpromazine (BZ) or other phenothiazines and benzidine or other xenobiotics mediated by soybean lipoxygenase (SLO) or purified human term placental lipoxygenase (HTPLO) in the presence of hydrogen peroxide, and the rates of xenobiotics oxidation were measured by spectroscopic analysis.

RESULTSChlorpromazine cation radical (CPZ(*+)) generated by lipoxygenase triggered a rapid oxidation of benzidine to benzidine diimine cation. Under the experimental conditions used, the metabolic interaction resulted in a 42-fold greater stimulation than BZ alone in the rate of BZ oxidation. The magnitude of stimulation of benzidine oxidation exhibited a dependence on the pH of the reaction medium, amount of the enzyme, and concentration of chlorpromazine, BZ, and hydrogen peroxide. A number of other phenothiazines were also found to stimulate BZ oxidation, albeit to a lesser degree. Chlorpromazine cation radical stimulated the oxidation of all six other xenobiotics tested. The highest stimulation (94-fold) was noted in the oxidation of tetramethyl phenylenediamine to Wursters blue radical, while the lowest stimulatory response (2-fold) was observed in guaiacol. Preliminary data showed that purified HTPLO also displayed a similar stimulatory response to benzidine oxidation in the presence of chlorpromazine.

CONCLUSIONBoth soybean lipoxygenase and purified human term placental lipoxygenase can mediate stimulatory response to the oxidation of benzidine and other xenobiotics in the presence of phenothiazines.

Benzidines ; metabolism ; Chlorpromazine ; chemistry ; Drug Interactions ; Female ; Humans ; Lipoxygenase ; isolation & purification ; pharmacology ; Oxidation-Reduction ; drug effects ; Phenothiazines ; pharmacology ; Placenta ; enzymology ; Pregnancy ; Xenobiotics ; metabolism

OBJECTIVEArylamine N-acetyltransferases (NATs) are involved in the detoxification of aromatic amines and hydrazine. In order to explore the possible association of NAT2 polymorphism with bladder cancer risk in benzidine exposed or non-exposed Chinese individuals, healthy subjects, subjects with bladder cancer of a former benzidine exposed cohort in Shanghai dyestuff industry and a group of bladder cancer patients without known occupational exposure to aromatic amines were genotyped for NAT2 gene polymorphism.

METHODSNAT2 genotyping was performed with a set of RFLP procedures at seven major polymorphic loci of gene coding area: G191A, C282T, T341C, C481T, G590A, A803G and G857A.

RESULTSThe wild allele NAT2 *4 was the most prevalent allele (59%) in healthy individuals. The alleles NAT2*6A and NAT2*7B were also frequently observed (21% and 17%, respectively). In contrast to Caucasians, the percentage of slow acetylators was lower (12% in Chinese vs. 58% in Caucasians, P < 0.001). No relevant differences were observed for homogenous rapid, heterogeneous rapid/slow and homogeneous slow acetylation genotypes between the healthy subjects and both groups of bladder cancer patients.

CONCLUSIONThe present work did not support the association of slow acetylating genotypes of NAT2 gene with elevated risk of bladder cancer in Chinese whereas it was documented as an important genetically determined risk factor in Caucasians. Different mechanisms might play a role in individual susceptibility to bladder cancer related with aromatic amine exposure in various races or ethnic groups.

Arylamine N-Acetyltransferase ; genetics ; Asian Continental Ancestry Group ; Benzidines ; toxicity ; Case-Control Studies ; Chemical Industry ; China ; epidemiology ; ethnology ; Coloring Agents ; Genetic Predisposition to Disease ; Genotype ; Humans ; Occupational Diseases ; epidemiology ; ethnology ; genetics ; Occupational Exposure ; Polymorphism, Genetic ; Urinary Bladder Neoplasms ; epidemiology ; ethnology ; genetics

The purpose of this study was to review occupational reproductive abnormalities and occupational bladder cancer in Korea and to discuss their toxicological implications. Reproductive dysfunction as a result of 2-bromopropane poisoning was first reported in Korean workers. In 1995, 23 of the 33 workers (25 female and 8 male workers) who were exposed to 2-bromopropane during the assembly of tactile switch parts developed reproductive and/or hematopoietic disorders. A total of 17 (68%) workers were diagnosed with ovarian failure. Two of the eight male workers experienced azoospermia and four workers experienced some degree of oligospermia or reduced sperm motility. In summary, 2-bromopropane poisoning caused severe reproductive effects in Korean workers. The prognosis was poor for reproductive dysfunction. A few cases of occupational bladder cancer have been reported in Korea, whereas other cancers of the urinary tract have not been reported after occupational exposure. A few cases of benzidine-induced cancer have been reported in Korea and 592 workers in Japan have received compensation for benzidine and beta-naphthylamine-induced cancer. In conclusion, a few cases of benzidine-induced occupational bladder cancer have been reported in Korea. However, benzidine-induced bladder cancer will likely be an important occupational health issue in Korea in the coming years.
2-Naphthylamine/toxicity ; Azoospermia/chemically induced/epidemiology ; Benzidines/toxicity ; Female ; Humans ; Hydrocarbons, Brominated/toxicity ; Infertility/*chemically induced/*epidemiology ; Male ; Occupational Diseases/*chemically induced/*epidemiology ; Occupational Exposure/adverse effects ; Oligospermia/chemically induced/epidemiology ; Primary Ovarian Insufficiency/chemically induced/epidemiology ; Republic of Korea ; Sperm Motility/drug effects ; Urinary Bladder Neoplasms/*chemically induced/*epidemiology