Intoxicación por tolueno / Toluene poisoning

Resumen El ser humano está inmerso en un entorno donde inhala, ingiere o absorbe muchas sustancias químicas, de las cuales toman relevancia las exposiciones en los lugares de trabajo y las que causan la muerte en la práctica médico forense. El tolueno es un inhibidor neuronal asociado con daño progresivo del sistema nervioso central y periférico, su toxicidad puede ocurrir por inhalación involuntaria o deliberada y puede llevar incluso a la muerte. Se realizó una revisión bibliográfica en diferentes bases de datos, de los artículos publicados referentes al tema de los últimos ocho años, con el objetivo de revisar las características del químico, el metabolismo, las intoxicaciones agudas y las crónicas, así como sus implicaciones letales. Se concluye que para mejorar la pericia médico legal, al valorar casos de intoxicacion por tolueno se deben de contemplar los criterios de causalidad en los casos de enfermedad laboral y en sospecha de causa de muerte es fundamentantal el resultado toxicológico ante la ausencia de hallazgos específicos en la autopsia.

Abstract The human being is immersed in an environment where he inhales, ingests or absorbs many chemical substances, in forensic medical practice the exposures in the workplace and those that cause death take on relevance. Toluene is a neuronal inhibitor associated with progressive damage of the central and peripheral nervous system, its toxicity can occur by involuntary or deliberate inhalation and can even lead to death. A bibliographic review was carried out in different databases, of the published articles referring to the subject of the last eight years, with the objective of reviewing the characteristics of the chemical, the metabolism, both acute and chronic poisoning and its lethal implications. It is concluded that to improve the legal medical expertise when assessing cases of toluene poisoning, causality criteria must be considered in cases of occupational disease and in suspected cases of death the toxicology result is fundamental in the absence of specific findings in the autopsy.

Maternal exposure to benzene and toluene and preterm birth. A longitudinal study

ABSTRACT BACKGROUND: Exposure to air pollutants has several effects on human health, including during pregnancy. OBJECTIVE: To identify whether exposure to benzene and toluene among pregnant women contributes to preterm delivery. DESIGN AND SETTING: Longitudinal study using data on newborns from mothers living in São José dos Campos (SP) in 2016, who had been exposed to benzene and toluene. METHODS: A logistic regression model with three hierarchical levels was constructed using maternal variables relating to newborns, and using benzene and toluene concentrations in quartiles. Occurrences of cesarean births, twins or malformations were excluded. Maternal exposure windows of 5, 10, 15, 30, 60 and 90 days prior to delivery were considered. RESULTS: Out of the 9,562 live births, 3,671 newborns were included and 343 newborns were born at less than 37 weeks of gestation (9.3%). The average birth weight was 3,167.2 g. Exposure to benzene and toluene was significantly associated (P = 0.04) with preterm delivery in the five-day window. There was no association in any of the other exposure windows. CONCLUSIONS: It was possible to identify that maternal exposure to benzene and toluene has an acute effect on preterm delivery.

Audição e exposição ao tolueno - uma contribuição para o tema / Audition and exhibition to toluene - a contribution for the theme

Introdução: Com os avanços tecnológicos e as mudanças nos processos produtivos, os trabalhadores estão expostos a diferentes agentes físicos e químicos em seu ambiente laboral. O tolueno é um solvente orgânico presente em colas, tintas, óleos, dentre outros. Objetivo: Comparar os achados literários que evidenciam que trabalhadores expostos simultaneamente a ruído e solventes têm maior probabilidade de desenvolverem uma perda auditiva de origem periférica. Método: Revisão de literatura a respeito da perda auditiva ocupacional em trabalhadores expostos a ruído e tolueno. Resultados: A exposição isolada ao tolueno também pode desencadear uma alteração dos limiares auditivos. Estes achados audiométricos, por ototoxicidade a exposição ao tolueno, apresentam audiogramas semelhantes ao por exposição ao ruído, o que torna dificultoso diferenciar um resultado audiométrico de exposição combinada - ruído e tolueno - e exposição apenas ao ruído. Conclusão: A maioria dos estudos foi projetado para gerar hipóteses e deveria ser considerado como passos preliminares de uma pesquisa adicional. Até hoje os agentes no ambiente de trabalho e seus efeitos têm sido estudados de maneira isolada e os limites de tolerância destes, não consideram as exposições combinadas. Considerando que os trabalhadores estão expostos a múltiplos agentes e que a perda auditiva é irreversível, os testes implementados devem ser mais completos e todos os trabalhadores devem fazer parte do programa de prevenção auditiva, mesmo expostos a baixas doses do limite de exposição recomendado...

Introduction: With the technological advances and the changes in the productive processes, the workers are displayed the different physical and chemical agents in its labor environment. The toluene is solvent an organic gift in glues, inks, oils, amongst others. Objective: To compare solvent the literary findings that evidence that diligent displayed simultaneously the noise and they have greater probability to develop an auditory loss of peripheral origin. Method: Revision of literature regarding the occupational auditory loss in displayed workers the noise and toluene. Results: The isolated exposition to the toluene also can unchain an alteration of the auditory thresholds. These audiometric findings, for ototoxicity the exposition to the toluene, present similar audiograms to the one for exposition to the noise, what it becomes difficult to differentiate a audiometric result of agreed exposition - noise and toluene - and exposition only to the noise. Conclusion: The majority of the studies was projected to generate hypotheses and would have to be considered as preliminary steps of an additional research. Until today the agents in the environment of work and its effect they have been studied in isolated way and the limits of tolerance of these, do not consider the agreed expositions. Considering that the workers are displayed the multiples agent and that the auditory loss is irreversible, the implemented tests must be more complete and all the workers must be part of the program of auditory prevention exactly displayed the low doses of the recommended limit of exposition...

Condição coclear e do sistema olivococlear medial de frentistas de postos de gasolina expostos a solventes orgânicos / Cochlear condition and olivocochlear system of gas station attendants exposed to organic solvents

INTRODUÇÃO: Solventes orgânicos são cada vez mais estudados em função de sua ação ototóxica. OBJETIVO: Avaliar a condição das células ciliadas externas e o sistema olivococlear medial de sujeitos expostos a solventes orgânicos. MÉTODO: Trata-se de um estudo prospectivo. Foram avaliados 78 frentistas de três postos de gasolina da cidade de Santa Maria, Rio Grande do Sul (RS) expostos a solventes orgânicos. Após a aplicação dos critérios de inclusão, a amostra ficou constituída por 24 sujeitos. Os procedimentos utilizados na avaliação foram anamnese audiológica, Emissões Otoacústicas Transientes (EOAT) e pesquisa do efeito supressor das EOAT. Um grupo controle (GC) composto por 23 sujeitos, foi utilizado para comparar sujeitos expostos e não-expostos. A coleta de dados foi realizada na sala de Fonoaudiologia do Centro de Referência em Saúde do Trabalhador de Santa Maria. RESULTADOS: A presença de EOAT foi maior na orelha esquerda em ambos os grupos; a média da relação sinal/ruído das EOAT de ambas as orelhas foi maior no GE; o efeito supressor das EOAT na orelha direita foi maior nos sujeitos do GE (62,5%) e na orelha esquerda foi superior no GC (86,96%), com diferença estatisticamente significante. A mediana da relação sinal/ruído das EOAT, segundo a faixa de frequência, foi maior no GC em três faixas de frequência na orelha direita e em uma na orelha esquerda. CONCLUSÃO: Não foram encontrados sinais de alteração nas células ciliadas externas nem no sistema olivococlear medial nos sujeitos expostos a solventes orgânicos.

INTRODUCTION: Organic solvents have been increasingly studied due to its ototoxic action. OBJECTIVE: Evaluate the conditions of outer hair cells and olivocochlear system in individuals exposed to organic solvents. METHOD: This is a prospective study. 78 gas station attendants exposed to organic solvents had been evaluated from three gas stations from Santa Maria city, Rio Grande do Sul (RS). After applying the inclusion criteria, the sample was constituted by 24 individuals. The procedures used on the evaluation were audiological anamnesis, Transient otoacoustic emissions (TEOAES) and research for the suppressive effect of TEOAES. A group control (GC) compounded by 23 individuals was compared to individuals exposed and non-exposed individuals. The data collection has been done in the room of Speech Therapy of Workers Health Reference Center of Santa Maria. RESULTS: The TEOAES presence was major in the left ear in both groups; the average relation of TEOAES signal/noise in both ears was greater in GE; the TEOAES suppressive effect in the right ear was higher in the individual of GE (62,5%) and in the left ear was superior in GC (86,96%), with statistically significant difference. The median sign/noise ratio of TEOAES, according to the frequency range, it was higher in GC in three frequencies ranges in the right ear and one in the left ear. CONCLUSION: It was not found signs of alteration on the outer hair cells neither on the olivocochlear medial system in the individuals exposed to organic solvents.

Occupational exposure of petroleum depot workers to BTEX compounds

Benzene, toluene, ethylbenzene and xylene [BTEX] are the most important toxic volatile compounds in the air and could be easily absorbed through the respiratory tract. In recent years, the risk of exposure to BTEX compounds, especially benzene as a carcinogen, has been considered in petroleum depot stations. To assess the occupational exposure of petroleum depot workers in Iran to BETX compounds. After completing a questionnaire and assessing occupational exposure to BETX compounds, 78 [46 exposed and 32 non-exposed] depot workers were randomly selected to participate in this study. Air sampling and analysis of BTEX was conducted according to the NIOSH method No. 1501. Analysis of urinary hippuric acid, as an indicator of toluene exposure, was carried out according to NIOSH method no. 8300. Personal monitoring of the high exposure group to BTEX compounds was repeated to verify the results obtained in the first phase of the monitoring. Among the 9 operating groups studied, occupational exposure to benzene and toluene was higher in quality control and gasoline loading operators - the median exposure ranged from 0.16 to 1.63 ppm for benzene and 0.2 to 2.72 ppm for toluene. Median exposure of other group members to BTEX compounds was below the detection limit of analytical method [0.07, 0.06, 0.05, and 0.05 ppm, respectively]. The level of toluene exposure measured showed correlation with neither post-shift urinary hippuric acid [Spearman's rho = 0.128, p=0.982] nor with the difference between post- and pr-shift urinary hippuric acid [Spearman's rho=0.089, p=0.847] in depot operational workers. Gasoline loading operators are exposed to a relatively high level of benzene

Abordagem inicial no atendimento ambulatorial em distúrbios neurotoxicológicos: parte III - solventes orgânicos / Initial approach to outpatient treatment of neurotoxicological disorders: Part III – organic solvents

Introdução: Milhões de pessoas são expostas diariamente aos solventes. Inúmeros solventes podem causar intoxicação aguda. Menos clara é a associação da exposição crônica e em baixas doses poder produzir alteração neurológica. Diversas atividades ocupacionais estão envolvidas com a sua exposição. Condição bastante diferente é o seu uso inadvertido com intuito alucinógeno. Método: Trata-se de revisão atualizada da literatura a partir de pesquisa na base de dados MEDLINE e LILACS. Também utilizou-se livros e documentos publicados em formato eletrônico.Discussão: Distúrbios neuromusculares, distúrbios do movimento, alterações cognitivo-comportamentais e neurofisiológicas têm sido relacionados a inúmeros agentes tóxicos nos últimos anos. A proposta deste artigo é revisar os principais distúrbios neurológicos associados à exposição crônica por solventes orgânicos. A fim de facilitar a abordagem inicial no atendimento ambulatorial aos distúrbios neurotoxicológicos foram confeccionadas tabelas descrevendo os principais agentes tóxicos, as fontes de exposição envolvidas e suas principais manifestações neurológicas. Conclusão: Tolueno, bissulfeto de carbono e n-Hexano são alguns solventes envolvidos nos distúrbios neurotoxicológicos, Contudo, fica evidente nesta revisão que são necessários novos estudos a fim de determinar a real associação destes e outros solventes nos distúrbios crônicos do sistema nervoso central e periférico.

Introduction: Millions of peoples are exposed to solvents every day. Most solvents cause acute intoxication. Less evident is the association of chronic exposure and in low doses in producing neurological disorders. Innumerable occupational activities are involved in the exposure to solvents. Their inadvertent use with hallucinogenous intention is an entirely different condition. Method: The method consists of an updated review of the literature based on research in the MEDLINE and LILACS databases, as well as books and documents published online. Discussion: Neuromuscular disorders, movement disorders, cognitive-behavioral and neurophysiological changes have been attributed to innumerable toxic agents in recent years. This article proposes to review the main neurological disorders associated with chronic exposure to organic solvents. To facilitate the initial approach to treatment of neurotoxicological disorders of outpatient, tables were devised to describe the main toxic agents, the sources of exposure involved and their main neurological manifestations. Conclusions: Toluene, carbon bisulfate and n-hexane are some of the solvents involved in neurotoxicological disorders. However, this review reveals the need for new studies to determine the real association of these and other solvents in chronic disorders of the central and peripheral nervous systems.

Exposición a solventes y disfunción auditiva central: revisión de la evidencia científica / Solvent exposure and central auditory dysfunction: a literature review on the scientific evidence

Diversos estudios han demostrado que los solventes orgánicos pueden inducir una disfunción auditiva. Los modelos animales han mostrado que los solventes son capaces de dañar las células ciliadas externas. Estudios de campo en trabajadores expuestos a solventes han encontrado por una parte, una mayor prevalencia de hipoacusia sensorioneural en comparación a grupos controles, y por otra, una dis función auditiva central asociada a la exposición a solventes. El presente trabajo tiene como objetivo revisar y discutir la evidencia científica acerca de la disfunción auditiva central asociada a la exposición a solventes como el tolueno, estireno, xileno, bisulfato de carbono, y mezcla de ellos. Se discuten los resultados de las investigaciones llevadas a cabo en humanos expuestos laboralmente a estos agentes. Se discuten además, los mecanismos de ototoxicidady neurotoxidad de los solventes y sus implicancias en la evaluación de la hipoacusia inducida por solventes.

Different studies have demonstrated that solvents may induce an auditory dysfunction. Animal models have shown that solvents can injure the outer hair cells. Studies conducted in workers exposed to solvents have found on one hand, a higher prevalence of sensorineural hearing loss in comparison to non-exposed control group subjects. On the other hand, these studies have found a central auditory dysfunction associated with solvent exposure. The present manuscript aims at revising and discussing the scientific evidence on central auditory dysfunction associated with exposure to solvents such as toluene, styrene, xylene, carbon disulphate, and mixtures. Results from studies conducted in humans occupationally exposed to solvents are discussed. Also, the oto-and neuro-toxicity induced by solvents and the implications for the assessment of solvent-induced hearing loss are addressed.

Hipoacusia por solventes orgánicos: enfermedad profesional inducida por la acción ototoxica de xilol & toluol: reporte de caso en Chile / Hearing loss due to organic solvent exposure: occupational disease induced by the ototoxic properties of xylene & toluene: Chilean case report

Se pone en conocimiento de la comunidad un caso de hipoacusia inducida por acción de solventes orgánicos (xilol, toluol), que forman parte de una investigación importante sobre patología ocupacional, pero que por el hecho de afectar directamente a un Tecnólogo Medico que se desempeña en un servicio de histopatología y citodiagnóstico, se considera relevante ponerla de manifiesto con el objetivo de alertar a los pares que se encuentren en iguales o similares condiciones de actividad laboral, para que tomen las medidas y resguardos necesarios respecto de su condición de trabajo y/o de salud.

Neurotoxicity risk of repeated exposure to inhalants: potential role of melatonin and vitamin B as neuron protectors

The main objective of the current study was to elucidate the neurotoxic effects induced by repeated exposure to gasoline, perchloroethylene or toluene on male rats. The study was extended to evaluate the interventive role of melatonin, folic acid and vitamin B12 against the neurodegenerative insult produced by inhalants abuse. Ten experimental groups were assigned as follows: group [1] control group; group[2] The rats were exposed to gasoline vapors [3200 ppm] for quarter an hour / day; group [3] The rats were exposed to gasoline vapors then treated with melatonin [10 mg / kg b. wt]; group [4] The rats were exposed to gasoline vapors then treated with folic acid [200 mg / kg b. wt] and vitamin B12 [o.o4 mg / kg b.wt]; group [5] The rats were exposed to perchloroethylene vapors [800 ppm] for quarter an hour/day; group [6] The rats were exposed to perchloroethylene vapors then treated with melatonin; group [7] The rats were exposed to perchloroethylene vapors then treated with folic acid and vitamin B12; group [8]. The rats were exposed to toluene vapors [1000 ppm] for quater an hour / day; group [9] The rats were exposed to toluene vapors then treated with melatonin and group [10] The rats were exposed to toluene vapors then treated with folic acid and vitamin B12. The experiment was extended for 45 days. Brain lipid peroxidation, reduced glutathione, serotonin, dopamine, and GABA were measured. In addition, plasma total testosterone and DHEA-S were determined. Histopathological investigation of the brain tissue was also carried out. The results demonstrated that inhalation of gasoline, perchloroethylene, or toluene causes elevation of brain lipid peroxidation, GABA and plasma DHEA-S levels. However, these inhalants induced depletion of brain reduced glutathione, serotonin, dopamine as well as plasma total testosterone levels. Histopathological alterations in the brain of the rats exposed to inhalants were also observed. On the other hand, marked improvement was detected on treatment of the exposed rats with either melatonin or folic acid and vitamin B12. Melatonin supplementation exerted a better modulatory effect on the most of the measured parameters in rats exposed to gasoline than rats exposed to gasoline and treated with folic acid and vitamin B12. Rats exposed to perchloroethylene or toluene then treated with folic acid and vitamin B12 revealed more pronounced improvement in the most of biochemical parameters than that detected by melatonin treatment. Histopathological investigation of the brain revealed that the treatment of rats exposed to gasoline with melatonin produced more pronounced modulatory effect than that in case of treatment with folic acid and vitamin B12 as indicated by the appearance of healthy neurons and astrocytes. However, treatment with folic acid and vitamin B12 to rats exposed to perchloroethylene showed more curative effect than that in case of treatment with melatonin as indicated by observing the neurons more or less like control. Also, the treatment with folic acid and vitamin B12 to rats exposed to toluene showed better effect than that in case of treatment with melatonin as indicated by the appearance of the neurons as much as control, except of few neurons that appeared with some degree of degeneration. The current results clearly indicated the serious effect of inhalants on the central nervous system of rats. Treatment with melatonin or vitamin B was found to have a modulatory action against inhalant neurotoxicity

High levels of hippuric acid in the urine of Thai press workers.

Toluene is an important toxic volatile agent found in many modern industrial processes. Toluene exposure is of particular concern because of the ongoing exposure of thousands of workers in industrial plants and recent research has indicated that toluene/exposure can result in chronic toxicity. The monitoring and control of toluene exposure among at-risk workers is necessary. Urine hippuric acid determination is a helpful test monitoring groups of at-risk workers. In this study, urine samples were obtained from 20 control subjects and 48 press workers from a factory in Bangkok. Each subject gave a specimen of urine; each specimen was analyzed for hippuric acid level by the Ohmori method. The average urine hippuric acid level in the control group was 0.23 +/- 0.15 mg/gCr (range = 0.05 - 0.58 mg/gCr) while that of the experimental group was 0.37 +/- 0.37 mg/gCr (range = 0.06 - 0.18 mg/gCr). A significant higher urine hippuric acid level among the press workers was found (p = 0.03). Based on this study, the prevention of exposure to toluene among high-risk workers is recommended.

The effect of cigarette smoking on urinary hippuric acid concentration in Thai workers with occupational exposure to toluene.

Urine hippuric acid determination is helpful for monitoring of group of workers at risk for exposure to toluene. However, some problems about the external source of variation are mentioned. Some studies have indicated that smoking is an important external source of variation for determination of urine hippuric acid level while the others stated the opposite findings. This study was conducted in an attempt to study the difference of urine hippuric acid between smoking and non smoking subjects in a press workers group. Urine samples were obtained from 46 workers (all male) who worked as press workers in the same press factory in Bangkok. The individuals were classified as control (non smoking, N = 26) and experimental (smoking, N = 20) according to their smoking. All samples were analyzed for hippuric acid level. The average urine hippuric acid level for the control were (0.35 +/- 0.31 mg/gCr) and experimental group (0.40 + 0.45 mg/gCr) were respectively. No significant difference was found between urine hippuric acid level between both groups. The data from the current study indicates that smoking does not influence the urinary hippuric acid levels in this study group.

Trabalhadores expostos simultaneamente a ruído e tolueno: estudo das emissöes otoacústucas evocadas e efeito de supressäo / Combined exposure to noise and toluene: study of the transient evoked otoacustic emissions and suppression

Objetivo: Estuda as emissöes otoacústicas evocadas transitórias (EOAET) e o efeito da supressäo em um grupo de indivíduos expostos simultaneamente a ruído e tolueno, comparando-o a outros dois grupos: expostos somente a ruído e näo expostos a ruído nem a tolueno, na busca de alternativas para a detecçäo precoce de alteraçöes auditivas e do melhor conhecimento do tipo de lesäo ocasionada pelo tolueno. Método: Neste estudo transversal, foram avaliados 140 indivíduos do sexo masculino com idades entre 18 e 48 anos de limiares audiométricos entre 0 e 25 dB NA, curva timpanométrica tipo A e reflexos acústicos presentes. Os indivíduos foram distribuídos em três grupo: a) sem exposiçäo a ruído e tolueno (n=40), b) expostos apenas a ruído, trabalhadores do setor de acabamento de uma indústria gráfica (n=50) e c) expostos simultaneamente a ruído e tolueno, trabalhadores do setor de rotogravura da mesma indústria (n=50). Além da anamnese clínica e ocupacional foram obtidos registros das emissöes otoacústicas transitórias na ausência e na presença de ruído branco contralateral de 50 dB NPS para verificaçäo do efeito de supressäo. Resultados: A prevalência de ausência de respostas nas EOAET em pelo menos uma das orelhas foi maior no grupo exposto a ruído e tolueno (64,0 por cento) e no grupo exposto apenas a ruído (62,0 por cento) que no grupo näo exposto (27,5 por cento). A prevalência de ausência do efeito de supressäo no grupo exposto simultaneamente a ruído e tolueno foi maior (48,9 por cento) em relaçäo aos expostos a ruído (17,4 por cento) e näo expostos (7,5 por cento). O risco de ausência de supressäo no grupo de expostos a ruído e tolueno foi expressivamente maior quando comparado aos näo expostos [odds ratio (OR) 11,70; intervalo de confiança de 95 por cento (IC 95 por cento) 3,17-43,49]. Conclusöes: Os resultados sugerem a existência de uma açäo neurotóxica do tolueno sobre a audiçäo afetando particularmente a porçäo retrococlear da via auditiva e ocasionando um tipo de lesäo distinta daquela provocada pelo ruído. O registro das EOAET e a análise do efeito de supressäo podem servir como instrumento importante na detecçäo precoce das alteraçöes auditivas de origem coclear e retrococlear e para a elaboraçäo de açöes preventivas em audiologia nos ambientes de trabalho

Intoxicação de escolares e adolescentes por inalação de cola de sapateiro

Este trabalho foi realizado com o objetivo de chamar atenção para o uso de cola de sapateiro por crianças e adolescentes e suas principais manifestações clínicas. É um estudo prospectivo, em pacientes consecutivos e não selecionados, admitidos no setor de emergência do Hospital Municipal Miguel Couto, com diagnóstico de intoxicação exógena por cola de sapateiro. Foram atendidos 29 pacientes. Estes foram classificados de acordo com a faixa etária, sexo, cor e manifestações clínicas. Houve predomínio do sexo masculino, faixa etária entre 16 anos, com maior incidência entre 12 e 14 anos. As manifestações mais comuns foram: agitação,cefáleia torpor e hipotensão arterial

Comparacao dos niveis de orto-cresol e acido hipurico na urina de trabalhadores expostos ao tolueno / Comparing levels of orto-cresol and hipuric acid in the urine of workers exposed to toluene

O tolueno e um solvente aromatico com larga utilizacao industrial, sendo usado na fabricacao de varios produtos como cola, tiner, tintas e outros. Sua acao neurotoxica constitui o principal risco a saude dos trabalhadores, tornando-se indispensavel medidas de controle e avaliacao da exposicao ocupacional...

Efectos neurotóxicos producidos por la inhalación temprana de solventes volátiles sobre el desarrollo neuronal y conductual de la rata / Neurotoxic effects induced by early solvent inhalation of neuronal and behavioral development of the rat

En el presente estudio experimental se evalúa el potencial efecto neurotóxico que produce la inhalación temprana de solventes orgánicos (principalmente tolueno) contenidos en adhesivos de uso comercial, sobre el desarrollo conductual y neuronal de la rata. Se utilizaron 135 ratas de la cepa Sprague-Dawley, divididas aleatoriamente en sujetos controles y tratados. Las ratas del grupo inhalador fueron expuestas a vapores de adhesivos entre los días postnatales 2 y 21 (período crítico del desarrollo cerebral). El día postnatal 22 se realizaron evaluaciones conductuales midiendo su capacidad exploratoria y ontogenia natatoria. Posteriormente fueron anestesiadas con éter, sacrificados y sus cerebros procesados con el método de Golgi-Cox-Sholl. Una vez delimitada la zona frontal, se dibujaron neuronas piramidales superficiales (capas II-III); estudiando su grado de diferenciación estructural (dendrogénesis). Los resultados obtenidos nos permiten concluir que la exposición temprana a estos solventes produce un significativo deterioro en el desarrollo neuronal y conductual

Cerebellar atrophy related to chronic exposure to toluene: case report

Uma mulher de 31 anos desenvolveu síndrome cerebelar e neurastênica, de evoluçäo lentamente progressiva, após 14 anos de exposiçäo ocupacional a vapores de toluenos em baixas concentraçöes. Os únicos achados do exame neurológico e neuropsicológico foram sinais cerebelares (severos) déficit visuo-espacial e práxico-construcional (moderado). A neuroimagem tomográfica mostrava acentuada atrofía e a neuroimagem (TC) estavam inalteradas, enquanto a funçäo visuo-construcional havia parcialmente melhorado. Os autores chamam a atençäo para o possível risco neurotóxico relacionado a esse tipo de exposiçäo, numa tentativa de prevençäo de casos semelhantes

Alteraciones neuropsicológicas en trabajadores expuestos a neurotóxicos / Neuropsychological disorders in workers exposed to neurotoxics

La neurotoxicidad es un grave problema de salud pública debido al incremento de sustancias neurotóxicas y a la gran cantidad de trabajadores expuestos. Gran cantidad de sustancias de uso común en la industria. Tales como solventes, metales y plaguicidas, provocan alteraciones neurotóxicas a concentraciones por debajo de los límites permisibles, produciendo cambios importantes en la función psicológica y el comportamiento, que se expresan en trastornos funcionales que interfieren en las tareas cotídianas e incrementan la accidentabilidad. En este artículo se revisa la literatura científica sobre los efectos neurotóxicos de solventes, plomo, mercurio y plaguicidas, y se comentan aspectos metodológicos de interés para el diseño de investigaciones epidemiológicas. Como conclusión, es notoria la existencia de evidencias que demuestran el efecto neurotóxico de gran cantidad de sustancias usadas en la industria. Así mismo, consideramos importante continuar realizando investigaciones sobre el tema, y sobre todo, La necesidad de tomar medidas preventivas para proteger la salud del trabajador

Investigación de los efectos neurofisiológicos de la inhalación aguda de neoprén en el gato / Investigation of the neurophysiological effects of acute neopren inhalation in the cat

En 15 gatos encéfalo aislados o curarizados, se estudiaron los fectos neurofisiológicos de la inhalación aguda de disolventes orgánicos de neoprén (Tolueno, n-hexano, benceno). La actividad eléctrica se registró medinate electrodos implantados estereotáxicamente en hipocampo, amígdalas, formación reticular mesencefálica y núcleo caudado. Se hizo monitoreo de EEG y ECG. El disolvente orgánico fue impulsado por medio de la ventilación mecánica. La actividad electrográfica de base durante los 30 a 40 min que duró cada sesión experimental, varió desde los signos de máxima alerta hasta intensificación de sincronización modulada que alternó con desincronización. Frecuentemente esta actividad estuvo desfasada entre las diversas estructuras estudiadas. Se observaron descargas paroxísticas parciales principalmente en hipocampo y amígdala. También se observaron descargas paroxísticas generalizadas con orígenes aparentes distintos. En cinco gatos se hizo fotoestimulación, en dos provocó paroxismos generalizados y en uno, crisis focal amigadliana. La frecuencia óptima fue de 3 Hz

Diferentes concentraciones de tolueno provocan el síndrome serotonérgico / Different concentrations of toluene inducing serotonergic syndrome

Los efectos sobre la conducta observados durante la inhalación de "thiner" han sido atribuidos al tolueno. Diversos estudios definen al tolueno como una droga alucinógena, que ejerce su efecto probablemente a través de mecanismos serotonérgicos. En este trabajo se estudia el efecto de la exposición aguda a diferentes concentraciones de tolueno en la presentación del síndrome serotonérgico. Grupos de ratas macho Wistar fueronm expuestos a diversas concentraciones de tolueno durante 15 minutos por única vez, mediante un sistema estático de inhalación. Se registró la presencia de los signos que integran al síndrome serotonérgico; además se evaluó el reflejo de enderezamiento. La concentración efectiva media de tolueno para provocar el síndrome serotonérgico fue de 4,878 ppm. El efecto observado sobre el reflejo de enderezamiento fue la perdida de éste a partir de 7,638 ppm; el efecto se incrementó de manera dependiente de la concentración

Efectos de la inhalación de tolueno sobre el sistema nervioso central / Toluene inhalation effects on central nervous system

El tolueno es un disolvente industrial que se encuentra en el "thinner" y en los pegamentos; es una sustancia que inhalan los niños y los adolescentes. Su efecto farmacológico tóxico radica en su acción sobre el sistema nervioso central modificando la fluidez de la membrana citoplasmática e induciendo la presencia de una curva dosisrespuesta bifásica. Devido a la importancia de este disolvente, se revisaron las alteraciones producidas por su inhalación a nivel morfológico, neurológico y electrofisiológico. Las lesiones morfológicas se caracterizan por ahuecamiento del tallo neuronal, hipertrofía fibrialr, vacuolización citoplasmática, picnosis, degeneración de fosfalíatrofia dendrítica y formación de placas de gliosis. A nivel neuroquímico se incrementa la N-metilación de fosfolípidos de membrana, y la descarboxilación de L-aminoácidos aromáticos; también se observan modificaciones en la afinidad y número de receptores, además de la concentración de dopamina, noradrenalina y serotonina, en niveles que dependen de la concentración y duración de la exposición. Los estudios electrofisiológicos indican una disminución de la actividad cerebral. Aun cuando no existe una correlación consistente entre las alteraciones neuroquímicas y los efectos de conducta, estudios recientes se orientan a considerar que la vía serotonérgica desempeña un papel importante en la intoxicación con tolueno.