Rapid determination of 30 volatile organic compounds in workplace air by gas chromatography / 中华劳动卫生职业病杂志

Objective: To establish a method for rapid detection of DB-WAX capillary column and determination of the workplace air in 30 kinds of volatile organic pollutants. Methods: In August 2020, N-pentane, n-hexane, methylcyclohexane, octane, Acetone, ethyl acetate, butanone, benzene, 3-pentanone, trichloroethylene, tetrachloroethylene, toluene, butyl acetate, 2-hexanone, Isoamyl acetate, ethylbenzene, p-xylene, m-xylene, amyl acetate, o-xylene, chlorobenzene, styrene, cyclohexanone, P-chlorotoluene, bromobenzene, M-dichlorobenzene, p-dichlorobenzene, O-dichlorobenzene, o-Chlorotoluene, 1, 2 , 4-trichlorobenzene of 30 kinds of substances in air were collected by activated carbon tube. After analysis by carbon disulfide, the analytical solution was analyzed by DB-WAX column and determined by FID detector. Results: The above 30 kinds of volatile organic pollutants had good separation effect, the correlation coefficient of the standard curve was above 0.999, the relative standard deviation was 0.1%-3.2%, the desorption efficiency was 77.0%-117.1% , the lower limit of quantitation was 0.33-5.33 μg/ml, and the lowest quantitation concentration was 0.22-3.55 mg/m(3), the recoveries ranged was 95.4%-104.9%. Conclusion: The method can effectively separate and accurately determine 30 volatile organic compounds in these workplaces, and the method is simple and quick.

Mitochondrial Toxins and Healthy Lifestyle Meet at the Crossroad of Hormesis

Mitochondrial function is crucial for the maintenance of cellular homeostasis under physiological and stress conditions. Thus, chronic exposure to environmental chemicals that affect mitochondrial function can have harmful effects on humans. We argue that the concept of hormesis should be revisited to explain the non-linear responses to mitochondrial toxins at a low-dose range and develop practical methods to protect humans from the negative effects of mitochondrial toxins. Of the most concern to humans are lipophilic chemical mixtures and heavy metals, owing to their physical properties. Even though these chemicals tend to demonstrate no safe level in humans, a non-linear dose-response has been also observed. Stress response activation, i.e., hormesis, can explain this non-linearity. Recently, hormesis has reemerged as a unifying concept because diverse stressors can induce similar stress responses. Besides potentially harmful environmental chemicals, healthy lifestyle interventions such as exercise, calorie restriction (especially glucose), cognitive stimulation, and phytochemical intake also activate stress responses. This conceptual link can lead to the development of practical methods that counterbalance the harm of mitochondrial toxins. Unlike chemical hormesis with its safety issues, the activation of stress responses via lifestyle modification can be safely used to combat the negative effects of mitochondrial toxins.

Inspección preliminar de algunas características de toxicidad en el agua potable domiciliaria, Bogotá y Soacha, 2012 / Preliminary survey to detect toxic substances in domestic potable water, Bogotá and Soacha, 2012

Introducción. La distribución y el almacenamiento del agua después de su potabilización, pueden originar cambios significativos en su calidad, por lo que es necesario conocer las características finales del agua domiciliaria que consumen los usuarios. Objetivo. Evaluar de forma preliminar las sustancias químicas tóxicas en el agua de tanques y grifos de viviendas abastecidas por el acueducto de Bogotá. Materiales y métodos. Se hizo un estudio descriptivo en 26 viviendas localizadas en Bogotá y Soacha. Se hicieron dos muestreos: uno en época de lluvias y otro en temporada seca, y en ambos se aplicó una encuesta y se recolectaron muestras de agua de los tanques de almacenamiento y los grifos. Las muestras se sometieron a ensayos fisicoquímicos básicos, a una prueba de tamización de sustancias orgánicas e inorgánicas, y a pruebas de determinación de metales pesados y de residuos de plaguicidas organofosforados y carbamatos. Resultados. La conductividad, el color y los nitratos presentaron valores permisibles; el pH y la turbiedad tuvieron una ligera tendencia a presentar niveles altos y, el cloro residual, niveles bajos. Hubo trazas de aluminio en el 94 % de las muestras. En el período seco, 8 % de las muestras presentó compuestos orgánicos y, en el período lluvioso, 66,7 %. Solo hubo un resultado positivo para las sustancias inorgánicas. En el 11,5 % de las viviendas, el nivel de riesgo fue medio, en el 61,5 %, bajo, y en el 27 % no se registró riesgo. Conclusiones. Se evidenció deterioro de la calidad del agua domiciliaria debido a la presencia de sustancias orgánicas en tanques y sobre todo en las redes, presumiblemente a causa de la formación de biopelículas o a la presencia de polímeros orgánicos. Los niveles de aluminio cercanos al máximo aceptable pueden explicarse por los remanentes de los coagulantes utilizados durante el tratamiento.

Introduction: Significant alterations may be found in the water of Bogotá´s water supply system after its purification, specifically during its distribution and storage in home reservoirs, which makes it necessary to study the final quality of the domiciliary water consumed by users. Objective: To conduct a preliminary study of toxic chemical substances in the water supplied by Bogotá´s water supply system in samples obtained from residential reservoirs and faucets. Materials and methods: Descriptive study made in 26 homes located in Bogotá and Soacha. Two samplings were done during different seasons, each including a survey and the collection of water samples from domiciliary storage tanks and faucets. Samples were analyzed for basic physicochemical parameters, a screening test for organic and inorganic substances and the determination of heavy metals and residues of organophosphate pesticides and/or carbamates. Results: Values obtained for conductivity, color and nitrates were acceptable, pH and turbidity were slightly high while residual chlorine levels were low; aluminum traces were found in 94% of the samples; 8% of the samples analyzed during the dry season showed organic compounds, compared to 66.7% during the rainy season, and just one positive result was obtained for inorganic compounds. Consequently, a medium risk level was observed in 11.5% of homes, low risk in 61.5% and no risk in 27.0%. Conclusion: The evidence showed deterioration of the domiciliary water by organic substances present in the reservoirs as well as in the water supply piping, probably caused by the formation of biofilms or organic polymers. Aluminum levels close to the top permissible limit can be explained by the presence of residual coagulants used during water treatment.

Analysis of parkin gene mutations in Han Chinese with sporadic early-onset parkinsonism in southern China / 中华神经科杂志

Objective To investigate the spectrum and features of parkin gene mutations in Chinese patients with sporadic early-onset Parkinsonism (EOP) in southern China.Methods All 156 Han Chinese patients with sporadic EOP were screened for mutations in parkin gene using SYBR Green Ⅰ Real-time PGR combined with sequencing of the entire coding region of the gene.Results Nineteen cases carried parkin mutations, including 2 homozygous, 2 compound heterozygous and 15 heterozygous mutations.Seventeen parkin gene rearrangement mutations ( 12 exon deletions and 5 exon duplications) and three small sequence mutations (ⅣS9 + 18C ＞ T,c.202-203delAG and c.813delT) were identified.The c.813delT is a novel mutation.The segment between exon 1 and 7 are mutational hot spot.Cases with parkin mutations showed no difference in initial symptoms, cardinal symptoms and disease severity, compared with cases without parkin mutations.But patients with parkin mutations showed significant earlier onset age ( ( 40.9 ± 6.8 ) years vs (35.5 ± 10.0) years, Z = -2.271, P ＜0.05) and longer disease duration ( (4.4 ±3.6) years vs (7.6 ±4.0) years,Z = - 3.680, P ＜ 0.05 ) than those without parkin mutation.Conclusions The frequency of parkin gene mutation was 12.18% in Han Chinese patients with sporadic EOP.Rearrangement mutation may be the predominant type of mutations.The exon deletion is a main mutation style.The sequence fragment between exon 1 and 7 of the parkin gene are mutational hot spots.There were no significant differences in clinical features between cases with parkin mutation and those without.However, our patient with parkin mutations showed a significantly earlier onset age, longer disease duration and slower progression than those without parkin mutation.

Identification and Analysis of Organic Pollutants in Child-Bearing Age Women Body / 环境与健康杂志

Objective To investigate the exposure levels of organic pollutants in child-bearing age women body. Methods The blood and urine specimens were collected simultaneously from each of 8 health women, aged 23-32 years, the organics were extracted with hexane and determined qualitatively by gas chromatography-mass spectrometer (GC-MS) for each specimen. Results In blood, 34 kinds of organic compounds had been detected , at average of (8.63?5.01 )kinds per person. Di-n-butyl phthalate (100%) and 14-bate-H-pregna (75.0%) revealed the highest detectable rates. In urine, 39 kinds of organic compounds had been identified, at average of (10.63?1.30) kinds per person, di-n-butyl phthalate(100%), HANFETT(100%), 14-bate-H-pregna(87.5%), docosane (87.5%), di-isobutyl phthalate(75.0%) were the chemicals noticed more frequently. Some kinds of these identified organics compounds were environmental toxic pollutants. Conclusion This study suggested that toxic organic pollutants had existed in child-bearing age women body, phthalic acid esters were the chemicals checked out more frequently. Their potential adverse health effects on women and offspring should be paid highly attention to.

Gene Polymorphism to the Effects of Low Level Aromatic Solvents Exposure on Spontaneous Abortion / 环境与健康杂志

Objective To investigate the association between genetic polymorphisms of cytochrome P450 MSP1 gene and the glutathione s-transferase GSTM1 gene in female workers exposed to aromatic solvents and spontaneous abortion. Methods A retrospective epidemiological investigation was carried out among 276 female workers including 58 female workers with history of spontaneous abortion and 218 female workers without spontaneous abortion selected in Yanshan of Beijing by the trained investigators using the unified questionnaire. Results The spontaneous abortion of female workers was significantly associated with GSTM1 (absent) (OR=2.07, 95% CI: 1.15-3.71), but not MSP1 (present) and exposure to aromatic solvent. After adust-ment for major confounders including education, age, shift work, body mass index, passive smoking and occupational stress, the multiple logistic regression analysis showed that GSTM1 gene (absent) significantly increased the risk of spontaneous abortion of female workers (OR=2.15, 95% CI: 1.17-3.98). Before and after adjustment for major confounders including education, age, shift work, body mass index, passive smoking and occupational stess, the multiple regression analysis showed that GSTM1 (absent) combined with MSP1 (heterozygous variant type / homozygous variant type) significantly increased the risk of spontaneous abortion (OR=2.98, 95% CI:l. 17-7.59), using the group with GSTM1 (present) and MSP1 (homozygous wild type) as reference group. Conclusion Our data suggested a genetic influence on spontaneous abortion in this population, GSTM1 (absent) was significantly associaled with spontaneous abortion, also provide evidence of additional joint action of gene MSP1 (heterozygous variant type and homozygous variant type) and GSTM1 (absent) to spontaneous abortion.