Tensión muscular percibida en operarias de máquinas de moldeo por inyección de plástico / Perceived muscle tension in female workers of plastic injection molding machines

OBJETIVO: Identificar la incidencia de Tensión Muscular Percibida (TMP) según edad, antigüedad y tipo de jornada en operarias de máquinas de moldeo por inyección de plástico. MÉTODOS: se aplicó el cuestionario Nórdico Estandarizado a 86 de 128 trabajadoras con mínimo 1 año de antigüedad. RESULTADOS: Según el estudio transversal, el 84,9% de trabajadoras presentó TMP, con mayor incidencia en aquellas de 40 años de edad o más (90,2%), y mayor aun en el grupo de 6 a 10 años de antigüedad en el puesto (93,2%). Respecto al tipo de jornada laboral, la mayor incidencia de TMP fue en trabajadoras del horario nocturno (95,2%). El segmento corporal más afectado fue el cuello (63%), seguido por hombros y manos/muñecas (60,3%, respectivamente), y columna lumbar (50,7%). Del total de operarias con TMP, el 64,4% refirió impedimento para el desempeño de su trabajo en el último año, mientras que el 80,8% indicó manifestaciones corporales durante la última semana. CONCLUSIONES: No hubo significancia estadística de TMP con respecto a edad (X2 = 1,798; p > 0,05) o jornadas de trabajo (X2 = 3,636; p > 0,05), pero sí en relación con antigüedad (X2 = 13,881; p < 0,05). Las posturas estáticas y movimientos repetitivos pueden ser algunos factores de riesgo ocupacionales causales de TMP.

OBJECTIVE: To identify relationships between Perceived Muscular Tension (PMT), age, time-on-job, and labor shifts for female operators of plastic molding injection machines. METHODS: a standardized Nordic questionnaire was administered to 86 of the 128 workers with at least 1 year on job. RESULTS: Cross-sectional study, of an average population of 39.9 years of age, yielded 84.9% of workers affected with PMT, with a higher incidence amongst individuals 40 years or older (90.2%). The highest incidence of affected individuals was noticed in the group with 6 to 10 years on the job (93.2%). With regards to work shift, the highest prevalence of TMP was amongst night shift workers (95.2%). Regarding the affected body part; neck (63%), followed by: (i) shoulders and (ii) hands / wrists (both with 60.3%), and lower back (50.7%). From those that reported PMT, 64.4% reported some impairment in the performance of their work duties in the past year, while 80.8% indicated having symptoms during the immediately preceding week. CONCLUSIONS: as it relates to PMT, there is no statistical significance for the variables age (X2 = 1.798, p > 0.05) or work shift (X2 = 3.636, p > 0.05). However, time-on-job (X2 = 13.881; p < 0.05) has statistical relevance.

Endoglucanase production with the newly isolated Myceliophtora sp. i-1d3b in a packed bed solid state fermentor

This work is aimed to produce endoglucanase through solid state fermentation in a packed bed bioreactor with the use of the fungus Myceliophtora sp. I-1D3busing a mixture of wheat bran (WB) and sugar cane bagasse (SCB) as culture medium. Preliminary tests were performed in polypropylene plastic bags, controlling the variables temperature (40, 45, and 50ºC), initial moisture content (75, 80, and 85%, w.b.), and weight proportion SCB/WB (1:1, 7:3, and 9:1). The highest enzyme activities in plastic bags were obtained using the substrate proportion of 7:3, 50ºC temperature, and 80% initial moisture content (878 U/grams of dry solid). High activities of filter-paper cellulase and xylanase were also obtained in plastic bags and some results are reported. For the packed bed experiments, the temperature (45 and 50ºC) and the air flow rate (80, 100 and 120L/h) were the controlled variables. Activity of endoglucanase was similar to plastic bag tests. A longitudinal gradient of moisture content, was observed increasing from the bottom to the top of the reactor, even though the longitudinal enzyme activity profile was flat for almost the whole bed. Air flow rate did not affect enzyme activity, while experiments carried out at 50ºC showed higher enzyme activities. The maximum temperature peak observed was at about 6ºC above the process temperature.

Prevalence of musculoskeletal disorders among plastics industry workers / Prevalência de distúrbios musculoesqueléticos em trabalhadores da indústria plástica

The prevalence of musculoskeletal disorders among workers in the plastics industry in Salvador, Bahia State, Brazil was estimated. Cases were defined by reported symptoms of pain in the previous 12 months, lasting more than a week or having monthly minimum frequency, which had given rise to restrictions at work or to seeking medical attention, or where respondents had a severity score greater than or equal to 3 (on a numerical scale of 0 to 5). A stratified proportional random sample of 577 workers was studied. The prevalence of musculoskeletal disorders, considering of all body segments, was 50.1 percent. The prevalence of musculoskeletal disorders was higher among women than among men at distal upper extremities (34.6 percent and 11.6 percent respectively) and also in the region of the neck, shoulder or upper part of the back (27.4 percent and 17.6 percent respectively). There was no difference between genders for the prevalence of lower back pain (21.2 percent and 21.4 percent respectively); 65 percent of cases in this region had reports of pain in the previous seven days. Due to the importance and prevalence of musculoskeletal disorders, it is necessary that their measurement in epidemiological studies be done properly.

Estimou-se prevalência de distúrbio musculoesquelético em trabalhadores da indústria de plástico, em Salvador, Bahia, Brasil. Casos foram definidos pelo relato de sintomas de dor nos últimos 12 meses, com duração maior do que uma semana ou freqüência mínima mensal, que haviam determinado restrição ao trabalho ou procura médica, ou tinham gravidade maior ou igual a 3 (numa escala numérica de 0 a 5). Estudou-se uma amostra aleatória estratificada proporcional de 577 trabalhadores. A prevalência de distúrbio musculoesquelético, considerando todos os segmentos corporais, foi de 50,1 por cento, sendo maior entre mulheres do que entre homens nas extremidades superiores distais (34,6 por cento e 11,6 por cento, respectivamente) e na região de pescoço, ombro ou parte alta do dorso (27,4 por cento e 17,6 por cento, respectivamente). Não houve diferença entre os sexos para a prevalência de lombalgia (21,2 por cento e 21,4 por cento, respectivamente) e 65 por cento dos casos nesta região apresentaram dor nos últimos sete dias. Devido à grande importância e prevalência dos distúrbios musculoesqueléticos, é necessário que a sua mensuração seja feita adequadamente, em estudos epidemiológicos.

Evaluación de un elevador neumático para carga de cabezal en área de printer en una empresa productora de tapas plásticas en Chile / Evaluation of a pneumatic elevator for head lifting in printer area at a plastic closure manufacturing company in Chile

Para lograr los objetivos de la política de seguridad y salud ocupacional de ALCOA CSI en Chile, el equipo de ergonomía de la Empresa desarrolló una intervención ergonómica en el área de trabajo de Printer (impresión). Esta área de producción presenta el riesgo de desarrollo de lesiones músculo-esqueléticas por el alto esfuerzo físico de extremidades superiores al manipular el cabezal de impresión de tapas. El propósito fue determinar las exigencias físicas, mentales, ambientales y organizacionales del trabajo, poniendo énfasis en las exigencias biomecánicas de hombros. A través de herramientas de evaluación ergonómica se determinó el nivel de esfuerzo físico ejercido por los hombros durante la realización de esta tarea. Se utiliza la Ecuación de carga de NIOSH, el Strain index, Sue Rodgers- fatigue y Rula antes y después de la instalación de un elevador mecánico del cabezal. Los resultados mostraron el alto riesgo de desarrollar lesiones tendinosas de hombros al cargar manualmente esta pieza, y la evidente reducción de este riesgo al implementar un elevador neumático, lo cual reduce la fuerza ejercida por los grupos musculares flexores, rotadores y elevadores de hombros, y las posturas anómalas asociadas con las extremidades superiores. Este resultado demuestra la importancia de realizar evaluaciones ergonómicas preventivas en los puestos de trabajo para cuantificarlas exigencias de tareas específicas e implementar medidas para prevenir o reducir lesiones músculo-esqueléticas, y con ello reducir los costos en salud para las empresas y sus trabajadores.

Negociaçäo coletiva e participaçäo na prevençäo de acidentes de trabalho / Colective negociation and participation in work acidents prevention

Analisa o caso da experiencia da implantaçäo da convençäo coletiva de segurança em máquinas injetoras de plástico em vigor no Estado de Säo Paulo.