Revisión bibliográfica no sistemática y comparada de la materia médica de Petroleum y de los cuadros clínicos generados por la exposición a hidrocarburos aromáticos / Non-systematic and comparative bibliographic review of Petroleum's medical material and clinical pictures generated by exposure to aromatic hydrocarbons

En este informe se presentan los resultados del cotejo de la pesquisa sobre la patogénesia de Petroleum y de los cuadros clínicos generados en las personas por la exposicion a los hidrocarburos aromáticos, para establecer la posibilidad de analogía entre los síntomas contenidos en la materia medica del Petroleum y los síndromes asociados a los efectos tóxicos de los hidrocarburos aromáticos; considerados por la O.M.S., la O.I.T y la A.T.S.D. R. como peligrosos y causantes de un problema global de salud pública. Se describen los mecanismos que soportan la reactividad biologica de la molécula de benceno, estructura básica y funcional de los hidrocarburos aromáticos, presente en el petróleo y la gasolina, reconocida como uno de los compuestos más tóxicos por sus propiedades carcinogénicas y capacidad de afectar procesos enzimáticos vitales llegando a causar mutaciones, enfermedades incapacitantes y dada su afinidad por el tejido graso, lesionar el Sistema Nervioso y el Sistema Neuroendocrino produciendo síndromes clínicos insidiosos y progresivos, agravados por hábitos de vida no saludables como el consumo de alcohol y el tabaquismo. Si bien es cierto que la descripción de los efectos (signos) en la salud provocados por la exposición a los hidrocarburos aromáticos no se encuentra modalizada, a diferencia de la descripción del síntoma en la semiología homeopática que permite la individualizacion, se infiere correspondencia entre la lesión orgánica y la consecuente expresión de déficit funcional del individuo y analogía con los síntomas descritos en la patogenesia del Petroleum. La lesión del Sistema Nervioso provocada por la exposición a los hidrocarburos aromáticos que comprometen al individuo desde su afecto, intelecto y voluntad explican las peculiaridades de sus síntomas mentales y los síntomas generales; asi mismo, los efectos sobre el sistema neuroendocrino se expresan en síntomas de déficit adaptativo; en piel y mucosas, se evidencian los efectos irritantes. Todo esto nos permite inferir el grado de analogía correspondiente con la patogenesia del medicamento Petroleum.

An Unexpected Death Related to Accidental Gasoline Inhalation / 대한법의학회지

Gasoline is a chemical compound of aliphatic and aromatic hydrocarbons, and it easily vaporizes because of its volatile characteristics. Gasoline inhalation may occur accidentally or intentionally in various situations which could result in acute non-lethal or lethal intoxication. Given that gasoline is widely used in everyday life, it is surprising that deaths related to gasoline inhalation rarely occur. We presented a rare case of unexpected death related to gasoline inhalation with the postmortem findings and features.

Early Liver and Kidney Dysfunction Associated with Occupational Exposure to Sub-Threshold Limit Value Levels of Benzene, Toluene, and Xylenes in Unleaded Petrol

BACKGROUND: Unleaded petrol contains significant amounts of monocyclic aromatic hydrocarbons such as benzene, toluene, and xylenes (BTX). Toxic responses following occupational exposure to unleaded petrol have been evaluated only in limited studies. The main purpose of this study was to ascertain whether (or not) exposure to unleaded petrol, under normal working conditions, is associated with any hepatotoxic or nephrotoxic response. METHODS: This was a cross-sectional study in which 200 employees of Shiraz petrol stations with current exposure to unleaded petrol, as well as 200 unexposed employees, were investigated. Atmospheric concentrations of BTX were measured using standard methods. Additionally, urine and fasting blood samples were taken from individuals for urinalysis and routine biochemical tests of kidney and liver function. RESULTS: The geometric means of airborne concentrations of BTX were found to be 0.8 mg m-3, 1.4 mg m-3, and 2.8 mg m-3, respectively. Additionally, means of direct bilirubin, alanine aminotransferase, aspartate aminotransferase, blood urea and plasma creatinine were significantly higher in exposed individuals than in unexposed employees. Conversely, serum albumin, total protein, and serum concentrations of calcium and sodium were significantly lower in petrol station workers than in their unexposed counterparts. CONCLUSION: The average exposure of petrol station workers to BTX did not exceed the current threshold limit values (TLVs) for these chemicals. However, evidence of subtle, subclinical and prepathologic early liver and kidney dysfunction was evident in exposed individuals.

Potencial de cepas fúngicas aisladas en el área de biotecnología fúngica. Primera parte: uso de hongos en biorremediación / Potential of fungal strains isolated in the area of ​​Fungal biotechnology. Part one: Use of fungi in bioremediation

El potencial de las cepas fúngicas en biorremediación, que han sido aisladas en el Instituto de Investigaciones Fármaco Bioquímicas (IIFB), es bastante amplio, se han encontrado cepas que han sido usadas en investigaciones a nivel internacional, tal es el caso de Bjerkandera sp BOL 13, un hongo aislado en un efluente contaminado con aceite en Oruro, con capacidad de degradar varios compuestos hidrocarbonados aromáticos policíclicos. En otro extremo de la nación se logró aislar Galerina sp., un hongo productor de lacasas, enzima importante en los procesos de decoloración.

The potential of fungi strains in biorremdiation that have been isolated in the Intiture of Research Pharmaceutical and Buiochemical (IIFB) is broad, it have been found strains that have been used in research at international level, as Bjerkandera sp BOL 13, a fungi isolated in an oil contaminated effluent, able to degrade polycycloic aromatic hydrocarbons. In other side of the country Galerina sp. was isolated, a laccase producing fungi, an enzyme important in decolorizing processes. contaminado con aceite en Oruro, con capacidad de degradar varios compuestos hidrocarbonados aromáticos policíclicos.

Design, synthesis and activity assessment of aryl-substituent benzyl acid targeting HIV gp41 / 南方医科大学学报

<p><b>OBJECTIVE</b>To synthesize novel aryl-substituent benzyl acid compounds targeting HIV gp41 and characterize their anti-HIV activities.</p><p><b>METHODS</b>Twelve analogues of aryl-substituent benzyl acid were designed and synthesized by Suzuki- Miyaura cross-coupling and Knoevenagel condensation reactions using halo-benzyl acid or 3-carboxybenzeneboronic acid as the raw material. The inhibitory activities of these compounds on gp41 six-helix bundle formation were tested by ELISA, and their anti-HIV activities were determined using a luciferase assay.</p><p><b>RESULTS</b>The structures of the compounds were characterized by nuclear magnetic resonance and mass spectrography. Among the 12 compounds, 5 (7b, 7c, 7d, 7e, and 7g) could inhibit the gp41 six-helix bundle formation, and 7d showed the most potent effect, and could also inhibit the replication of HIV-1 SF33 strain with an IC(50) of 20 µmol/L.</p><p><b>CONCLUSION</b>The synthesized aryl-substituent benzyl acid compound 7d could inhibit HIV replication by blocking the gp41 six-helix bundle formation.</p>

[Assessment of Hematotoxic effects of occupational exposure to unleaded petrol]

Gasoline is a complex mixture of more than 500 hydrocarbons. The elimination of lead from petrol has been associated with the addition of significant amounts of hematotoxic monocyclic aromatic hydrocarbons such as benzene, toluene and xylene [BTX]. The main purpose of this study was to ascertain whether exposure to unleaded petrol, under normal working conditions, is associated with any hematotoxic response. This was a historical cohort study in which 200 subjects with current exposure to unleaded petrol from Shiraz petrol stations as well as 200 unexposed employees were investigated. Using standard methods, atmospheric concentrations of BTX were measured. Additionally, blood samples were taken from subjects for routine biochemical tests such as RBC, WBC and platelet count, Hemoglobin, hematocrit and RDW. The geometric means of airborne concentrations of BTX were found to be 0/24, 0/37 and 0/64 ppm, respectively. The results of blood chemistry tests showed that no significant differences exist between both groups as far as biochemical tests, but RDW and hematocrit, were concerned. The average exposure of petrol station workers to BTX did not exceed the current TLVs for these chemicals. Additionally, overt hematotoxicity is unlikely to be the outcome of exposure to unleaded petrol under the conditions described in our study.

The Characteristics of the Appearance and Health Risks of Volatile Organic Compounds in Industrial (Pohang, Ulsan) and Non-Industrial (Gyeongju) Areas

OBJECTIVES: The aim of this study was to identify the health and environmental risk factors of air contaminants that influence environmental and respiratory diseases in Gyeongju, Pohang and Ulsan in South Korea, with a focus on volatile organic compounds (VOCs). METHODS: Samples were collected by instantaneous negative pressure by opening the injection valve in the canister at a fixed height of 1 to 1.5 m. The sample that was condensed in -150degrees C was heated to 180degrees C in sample pre-concentration trap using a 6-port switching valve and it was injected to a gas chromatography column. The injection quantity of samples was precisely controlled using an electronic flow controller equipped in the gas chromatography-mass spectrometer. RESULTS: The quantity of the VOC emissions in the industrial area was 1.5 to 2 times higher than that in the non-industrial area. With regards to the aromatic hydrocarbons, toluene was detected at the highest level of 22.01 ppb in Ulsan, and chloroform was the halogenated hydrocarbons with the highest level of 10.19 ppb in Pohang. The emission of toluene was shown to be very important, as it accounted for more than 30% of the total aromatic hydrocarbon concentration. CONCLUSIONS: It was considered that benzene in terms of the cancer-causing grade standard, toluene in terms of the emission quantity, and chloroform and styrene in terms of their grades and emission quantities should be selected for priority measurement substances.

Structure, catalytic mechanism and applications of laccases: a review / 生物工程学报

Laccases (benzenediol: oxygen oxidoreductases; EC 1.10.3.2) are copper-containing polyphenol oxidases that can oxidize a wide range of aromatic compounds, concomitantly with the transfer of four electrons and the reduction of molecular oxygen to water. The progress on the research of laccases structure and function is reviewed. Their three-dimensional structures and catalytic mechanism, as well as their applications in different fields are emphasized.

The Effects of Long-Term, Low-Level Exposure to Monocyclic Aromatic Hydrocarbons on Worker's Insulin Resistance

OBJECTIVES: This study was designed to investigate whether long-term, low-level exposure to monocyclic aromatic hydrocarbons (MAHs) induced insulin resistance. METHODS: The subjects were 110 male workers who were occupationally exposed to styrene, toluene, and xylene. One hundred and ten age-matched male workers who had never been occupationally exposed to organic solvents were selected as a control group. Cytokines, which have played a key role in the pathogenesis of insulin resistance, and oxidative stress indices were measured. Assessment of exposure to MAHs was performed by measuring their ambient levels and their urinary metabolites in exposed workers, and the resulting parameters between the exposed group and non-exposed control groups were compared. RESULTS: There was no significant difference in general characteristics and anthropometric parameters between the two groups; however, total cholesterol, fasting glucose, fasting insulin, and homeostasis model assessment of insulin resistance levels were significantly higher in the exposed group. Phenylglyoxylic acid levels showed significant association with tumor necrosis factor-alpha, total oxidative status, and oxidative stress index via multiple linear regression analysis. Further, there was a negative correlation between methylhippuric acid levels and total anti-oxidative capacity, and there was a significant relationship between MAHs exposure and fasting glucose levels, as found by multiple logistic regression analysis (odds ratio = 3.95, 95% confidence interval = 1.074-14.530). CONCLUSION: This study indicated that MAHs increase fasting glucose level and insulin resistance. Furthermore, these results suggested that absorbing the organic solvent itself and active metabolic intermediates can increase oxidative stress and cytokine levels, resulting in the changes in glucose metabolism and the induction of insulin resistance.

Simultaneous determination of seven chemicals of halogenated alkanes and aromatic hydrocarbons in the air of workplace by gas chromatography / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish a gas chromatographic method for determination of halogenated alkanes and aromatic hydrocarbons including trichloromethane, 1,2-dichloroethane, carbon tetrachloride, benzene, toluene, ethylbenzene and xylene in the air of workplace.</p><p><b>METHODS</b>After the air samples collected with activated carbon tubes and desorbed with CS(2), the target toxicants were separated with FFAP capillary columns and detected with flame ionization detector.</p><p><b>RESULTS</b>The coefficient of correlation was above 0.999 and the lowest detectable concentrations were 0.2 ∼ 3.6 mg/m(3) with the RSD of 1.2% ∼ 4.6%. The desorption efficiencies was 94.9% ∼ 100.7%.</p><p><b>CONCLUSION</b>The method shows lower detection limit, high accuracy and precision. It is feasible for determination of the seven halogenated alkanes and aromatic hydrocarbons in the air of workplace.</p>

Influence of Epinephrine and Norepinephrine on the Risk of Metabolic Syndrome Occurrence in Workers Exposed to Hazardous Chemicals / 산업간호학회지

PURPOSE: The aim of the present study was to clarify effects of long term, low-level monocyclic aromatic hydrocarbons exposure (MAHs) such as styrene, toluene and xylene on physiological levels of epinephrine (EP) and norepinephrine (NEP) and these hormones influences diagnosis indices of metabolic syndrome (MetS). METHODS: Blood pressure and serum biochemical parameters were measured using digital sphygmomanometer and autochemical analyzer. EP and NEP were analyzed by using ELISA kit and exposure level of MAHs was measured by NIOSH method. RESULTS: The differences of general characteristics such as age, smoking and drinking habits in both groups were not significantly different except working hours per day. In exposed workers, exposure levels of MAHs showed very low concentrations. Serum HDL-cholesterol concentration was significantly higher in exposed group, but concentration of NEP was significantly higher in control group. On multiple logistic regression analysis for the diagnosis indices of MetS, EP was WC (OR=0.970), NEP was blood pressure (OR=1.002) and MAHs exposure were significantly associated with HDL-cholesterol (OR=0.257), fasting glucose (OR=3.028) and MetS (OR=0.372). CONCLUSION: These findings suggest that the chronic exposure of low level MAHs maycontribute to glucose metabolism and induction of MetS. And also, changes of EP and NEP levels by exposure of MAHs affect blood pressure.

Isolation and characterization of a novel strain of Stenotrophomonas maltophilia possessing various dioxygenases for monocyclic hydrocarbon degradation / Isolamento e caracterização de uma nova cepa de Stenotrophomonas maltophilia com várias dioxigenases para degradação de hidrocarbonetos monocíclicos

A Gram-negative bacterium, designated as strain KB2, was isolated from activated sludge and was found to utilize different aromatic substrates as sole carbon and energy source. On the basis of morphological and physiochemical characteristics and 16S rRNA gene sequence analysis, the isolated strain KB2 was identified as Stenotrophomonas maltophilia. Strain KB2 is from among different Stenotrophomonas maltophilia strains the first one described as exhibiting the activities of three types of dioxygenases depending on the structure of the inducer. The cells grown on benzoate and catechol showed mainly catechol 1,2- dioxygenase activity. The activity of 2,3-dioxygenase was detected after phenol induction. Protocatechuate 3,4-dioxygenase was found in crude cell extracts of this strain after incubation with 4-hydroxybenzoic acid, protocatechuic acid and vanillic acid. Because of broad spectrum of dioxygenases' types that Stenotrophomonas maltophilia KB2 can exhibit, this strain appears to be very powerful and useful tool in the biotreatment of wastewaters and in soil decontamination.

Uma bactéria Gram-negativa, denominada KB2, foi isolada de lodo ativado, verificando-se ser capaz de utilizar substratos aromáticos com única fonte de carbono e energia. Com base nas características morfológicas e físico-químicas, e na análise da sequencia do gene 16SrRNA, esta bactéria foi identificada como Stenotrophomonas maltophilia. Entre as diversas cepas de S. maltophilia já descritas, essa cepa é a primeira com atividade de três tipos de dioxigenases, dependendo da estrutura do indutor. As células cultivadas em benzoato e catecol apresentaram atividade de catecol 1,2-dioxigenase principalmente. A atividade de 2,3-dioxigenase foi detectada após indução com fenol. Após incubação com ácidos 4-hidrobenzoico, ácido protocatecuico evanílico, encontrou-se protocatecuato 3,4-dioxigenase no extrato celular. Devido ao amplo espectro de atividade das diferentes dioxigenases de S. maltophilia KB2, esta cepa parece ser uma ferramenta poderosa e útil para o biotratamento de efluentes e descontaminação do solo.

A Case of Lung Necrosis and Abscess after Paint Thinner Ingestion

Paint thinners contain a mixture of volatile organic solvents, including aromatic hydrocarbons such as toluene, xylene, and N-hexane. Hydrocarbon pneumonitis is an acute, intense pneumonitis resulting from the aspiration of volatile hydrocarbon compounds with low viscosity and surface tension. Here we report the case of a 60-year-old man admitted to our hospital with chest pain following the ingestion of paint thinner. Aspiration resulted from inducing emesis after ingestion. Acute chemical pneumonitis developed in the right lower lung. The patient's course was further complicated by lung necrosis, abscess, pleural effusion, and pneumothorax. He was treated with pleural adhesiolysis and a right middle lobe wedge resection via video-assisted thoracoscopic surgery.

effect of industrial waste of oil companies on the distribution of organic pollutants in Ismailia Canal Water

Survey for Ismailia Canal fresh water indicated normal conditions for physico-chemical parameters. Total dissolved solids and all cations and anions were within the acceptable limits. The concentration of n-alkanes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons [PAHs] and chlorinated hydrocarbons were detected in three sites. Site 1 [intake of Mostorod drinking water treatment plant], Site 2 [after oil companies], and site 3 in the middle of the canal. Site 2 had the highest concentrations of the studied hydrocarbons due to drainage of the oil from oil companies and discharge of the industrial waste from other companies into the canal water. The concentrations of organic compounds were decreased after that due to dilution. The concentration of chlorinated hydrocarbons was too much lower than that of n-alkanes, aromatic hydrocarbons and PAHs

GC-MS analysis of essential oil from nutmeg processed by different traditional methods / 中国中药杂志

<p><b>OBJECTIVE</b>To analyze the chemical components of the essential oil extracted from the seeds of Myristica fragrans (nutmeg) processed by different methods (steamed with water steam, roasted with flour, sauted with flour, roasted with talcum powder, roasted with loess, and roasted with bran) and to provide quality control foundations in the sciences.</p><p><b>METHOD</b>The essential oil was extracted by steam distillation and separated with GC capillary column. The relative content of every compound was determined with area normalization method and the structures were elucidated by GC-MS technique.</p><p><b>RESULT</b>Fifty-eight to one hundred and four of chromatographic peaks were detected, among them seventy-six compounds accounting for 98.32% to 99.99% of the total essential oil in nutmeg were identified, which were composed of 69.15% to 97.24% for monoterpenoids and 2.06% to 25.51% for aromatic compounds of the total essential oil, respectively.</p><p><b>CONCLUSION</b>It was shown that monoterpenoids and their derivatives were main composition, and aromatic compounds were secondary composition in the total essential oil of nutmeg grows in Indonesia and processed by different traditional methods on the basis of theory of traditional Chinese medicine. In addition, it was suggested that we should be careful to use processed nutmeg owing to contain safrole and a-asarone induced genetoxicity in animals and mutagenicity in the Ames Salmonella assay, and myristicin and elemicin induced narcotism in human. The processed method roasted with bran for nutmeg may be better and will be developed.</p>

Toxicity assessment and microbial degradation of azo dyes.

Toxic effluents containing azo dyes are discharged from various industries and they adversely affect water resources, soil fertility, aquatic organisms and ecosystem integrity. They pose toxicity (lethal effect, genotoxicity, mutagenicity and carcinogenicity) to aquatic organisms (fish, algae, bacteria, etc.) as well as animals. They are not readily degradable under natural conditions and are typically not removed from waste water by conventional waste water treatment systems. Benzidine based dyes have long been recognized as a human urinary bladder carcinogen and tumorigenic in a variety of laboratory animals. Several microorganisms have been found to decolourize, transform and even to completely mineralize azo dyes. A mixed culture of two Pseudomonas strains efficiently degraded mixture of 3-chlorobenzoate (3-CBA) and phenol/cresols. Azoreductases of different microorganisms are useful for the development of biodegradation systems as they catalyze reductive cleavage of azo groups (-N=N-) under mild conditions. In this review, toxic impacts of dyeing factory effluents on plants, fishes, and environment, and plausible bioremediation strategies for removal of azo dyes have been discussed.

Assessment of occupational exposure to VOCs at the Gantry gasoline Terminal.

The gasoline components dispersed in the workplace environment have direct impact on human health because of their carcinogenic and mutagenic potential. The volatile portion of these compounds generally consists of a mixture of monoaromatics such as benzene, toluene, ethylbenzene, xylenes and substituted benzene compounds. Investigation of levels of these chemicals at the petroleum liquid storage, and distribution facilities is of growing importance for assessing the occupational exposure of workers at these locations. A continuous monitoring was conducted at the Gantry Terminal of a refinery with portable samplers for determining 8-hr TWA at various locations involving petroleum liquid loading and distribution in road tank trucks, rail cars, and drums. After thermal desorption, the concentrations were determined in the laboratory with advanced Varian Model 2200GC/MS system. TVOCs level ranged between 0.10 to 1.97 mg/m3.The 8-hr TWA for benzene, toluene, and xylenes were low and within the limits for occupational exposure of gasoline components.

Bioremediación de suelos contaminados con hidrocarburos derivados del petroleo / Bioremediation of contamined soils with hidrocarbons derived from petroleum

El manejo inadecuado de los materiales y residuos peligrosos ha generado a escala mundial, un problemade contaminación de suelos, aire y agua. Entre las más severas contaminaciones se destacan las que seprodujeron y todavía se producen a causa de la extracción y el manejo del petróleo en todos los países productores de hidrocarburos. En nuestro país, el transporte de crudo y sus derivados se ha visto afectado considerablemente durante los últimos 18 años, por una permanente actividad terrorista contra los oleoductos e instalaciones petroleras. En el suelo los hidrocarburos impiden el intercambio gaseoso con la atmósfera, iniciando una serie de procesos físico-químicos simultáneos como evaporación y penetración, que dependiendo del tipo de hidrocarburo, temperatura, humedad, textura del suelo y cantidad vertida puede ser mas o menos lentos, ocasionando una mayor toxicidad, además de tener una moderada, alta o extrema salinidad, dificultando su tratamiento. Altos gradientes de salinidad pueden destruir la estructura terciaria de las proteínas, desnaturalizar enzimas y deshidratar células, lo cual es letal para muchos microorganismos usados para el tratamiento de aguas y suelos contaminados. En la presente revisión se analiza la biorremediacion como una alternativa saludable frente al deterioro progresivo de la calidad del medio ambiente por el derramamiento de crudos, ya que la esta problemática genera una amenaza real a la salud publica, así como la extinción de gran cantidad de especies vegetales y animales.

Transcriptional regulation of catabolic pathways for aromatic compounds in Corynebacterium glutamicum

Corynebacterium glutamicum is a gram-positive soil microorganism able to utilize a large variety of aromatic compounds as the sole carbon source. The corresponding catabolic routes are associated with multiple ring-fission dioxygenases and among other channeling reactions, include the gentisate pathway, the protocatechuate and catechol branches of the beta-ketoadipate pathway and two potential hydroxyquinol pathways. Genes encoding the enzymatic machinery for the bioconversion of aromatic compounds are organized in several clusters in the C. glutamicum genome. Expression of the gene clusters is under specific transcriptional control, apparently including eight DNA-binding proteins belonging to the AraC, IclR, LuxR, PadR, and TetR families of transcriptional regulators. Expression of the gentisate pathway involved in the utilization of 3-hydroxybenzoate and gentisate is positively regulated by an IclR-type activator. The metabolic channeling of ferulate, vanillin and vanillate into the protocatechuate branch of the beta-ketoadipate pathway is controlled by a PadR-like repressor. Regulatory proteins of the IclR and LuxR families participate in transcriptional regulation of the branches of the beta-ketoadipate pathway that are involved in the utilization of benzoate, 4-hydroxybenzoate and protocatechuate. The channeling of phenol into this pathway may be under positive transcriptional control by an AraC-type activator. One of the potential hydroxyquinol pathways of C. glutamicum is apparently repressed by a TetR-type regulator. This global analysis revealed that transcriptional regulation of aromatic compound utilization is mainly controlled by single regulatory proteins sensing the presence of aromatic compounds, thus representing single input motifs within the transcriptional regulatory network of C. glutamicum.

Audiometric findings in petrochemical workers exposed to noise and chemical agents.

This study investigated the occurrence of hearing loss among workers of a petrochemical industry during a period of five years. The records of environmental noise and solvents measurements and the results of annual audiometry performed by the company were examined. The audiometric results of workers from olefin operational areas 1 and 2 and aromatic plant areas exposed to solvents and noise and utility area workers exposed only to noise were analyzed for the standard threshold shift (STS). Despite the low exposures to solvents and a moderate exposure to noise, 45.3% of workers had hearing losses and 29.6% had STS.