Elements in human placentae in Jamaica / Elementos en las placentas humanas en Jamaica

AIM: To investigate the relationships, if any, between elemental content of the placenta with age of mother, birthweight and the Apgar scores of a neonate. METHODS: Placental samples were collected, stored at -20ºC and then dried and analysed using neutron activation with the SLOWPOKE II reactor at the International Centre for Environmental and Nuclear Sciences (ICENS). A questionnaire was administered at the time of delivery to determine the level of fish consumption, numbers of dental amalgam fillings and use of cough syrups. Placental concentrations of bromine, calcium, chlorine, iron, mercury, potassium, rubidium, selenium, sodium and zinc were determined. RESULTS: The placentae of 52 Jamaican mothers with a mean age 29 years (range 18-42 years) delivering singleton neonates with a mean birthweight of 3.1 kg (1.3 - 5.5 kg) at term were collected. With the exception of iron and bromine, all results for elemental determinations are very similar to those found elsewhere. Correlation was observed for Apgar 2 (5 minutes), calcium and zinc with birthweight, with p-values of 0.002, 0.007 and 0.07, respectively. Negative correlation was observed for the Apgar 2 and potassium (p = 0.056) and age of mother at birth and bromine (p = 0.02). The mercury concentration in the measured placentae (7.29 ±9.1 µg/kg w/w) was slightly lower than the mean concentration found in the literature (8 µg/kg w/w). Approximately 93% of the measured placentae in this study are below the derived placentae upper limit of 22 µg/kg. Of the 7% above the upper limit none exceeded the conservative estimated limit of 115 /µg/kg at which neural developmental problems start. CONCLUSION: The significant associations noted are of unknown clinical relevance and need further study.

OBJETIVO: Investigar las relaciones que pudieran existir entre el contenido elemental de la placenta y la edad de la madre, el peso al nacer, y la puntuación Apgar del neonato. MÉTODOS: Muestras de placenta fueron recogidas, almacenadas a -20ºC y entonces secadas y analizadas usando la activación neutrónica con el reactor SLOWPOKE II del Centro Internacional de Ciencias Medioambientales y Nucleares (ICENS). A la hora del parto se aplicó una encuesta para determinar el nivel de consumo de pescado, el número de amalgamas dentales y el uso de jarabes para la tos. Se determinaron las concentraciones placentales de bromo, calcio, cloro, hierro, mercurio, potasio, rubidio, selenio, sodio y cinc. RESULTADOS: Se recogieron las placentas de 52 madres jamaicanas con una edad promedio de 29 años (rango 18-42 años) que parieron neonatos únicos con un peso promedio de 3.1 kg (1.3-5.5 kg) a término. Con la excepción del hierro y el bromo, todos los resultados para las determinaciones elementales son muy similares a los hallados en otras partes. Se observó una correlación de Apgar 2 (5 minutos), el calcio y el cinc con el peso al nacer, los valores p de 0.002, 0.007 y 0.07 respectivamente. Se observó una correlación negativa de Apgar 2 y el potasio (p = 0.056) y la edad de la madre a la hora del alumbramiento, con el bromo (p = 0.02). La concentración de mercurio en las placentas medidas (7.29 ± 9.1 w/w de µg/kg) fue ligeramente más baja que la concentración promedio hallada en la literatura (8 µg/kg w/w). Aproximadamente 93% de las placentas evaluadas en este estudio están por debajo del límite superior de 22 µg/kg. Del 7% por encima del límite superior, ninguna excedió el límite conservador estimado de 115 µg/kg en el cual comienzan los problemas del desarrollo neural. CONCLUSIÓN: Se desconoce la importancia clínica de las asociaciones significativas observadas y se requiere más estudio.

Acute lead poisoning associated with backyard lead smelting in Jamaica / Envenenamiento agudo con plomo asociado con la fundición casera de plomo en Jamaica

Long-term backyard smelting of lead in a district known as Mona Commons, Kingston, Jamaica, has produced lead burdens as high as 30 000 mg/kg in soils near to the smelter, and indoor dust loadings of 373 microg/f2 in the residents' home. The blood lead levels (BPb) of 107 children from the district were in the range 2.2-202 microg/dL. Fifty-nine per cent of these had BPb levels above 10 microg/dL and the population mean was an unacceptably high 25.1 microg/dL. The highest levels were observed for five siblings, two of whom presented with lead encephalopathy. This severe chronic exposure to lead was exacerbated by a significant history of pica, and chronic nutritional anaemia. Chelation therapy significantly reduced the BPb levels but due to lead storage in other organs, the values after several months were still higher than desirable. This study emphasizes the importance of reducing the exposure of children to lead.

Cadmium levels in kidney and liver of Jamaicans at autopsy

The cadmium concentrations in the kidneys and livers of 39 autopsy cases in Jamaica, in the age group > or = 40 years, are renal cortex: range 6.7-126 mg kg-1, mean 43.8 mg kg-1; liver: range 0.3-24.3 mg kg-1, mean 5.3 mg kg-1. The mean levels in the renal cortex are higher for women than for men but not so significantly, nor are the differences between smokers and non-smokers clear. The observed values are considered high, second only to Japan where cadmium related health impairments have occurred, and nearly twice as high as the values reported from Austria, Australia, the United Kingdom and Sweden. The Jamaican cases were from areas with relatively low soil-cadmium concentrations, and the corresponding values are likely to be significantly higher in central Jamaica where the soil contains unusually high levels of cadmium. An examination of possible contributions of cadmium intake to renal problems in Jamaica now appears to be necessary

Blood lead levels in children in Jamaican basic schools

Blood lead levels (BLL) for 285 children, three to six years old, from seven basic schools located in known areas of anthropogenic pollution, and in urban and rural areas are reported. The samples were obtained by the finger-prick method and analyzed for lead by anodic stripping voltammetry. The majority of the children had blood lead levels below the now accepted limit of 10 micrograms dL-1 and there was no indication of cases that would represent medical emergencies. The present results show considerable improvement in the BLLs of children living in contaminated sites indicating the effectiveness of the previous remediation steps. Follow-up intervention work is in progress for cases of blood lead levels in excess of the recommended limit

Trace elements in Jamaican tobacco

The concentrations of 28 elements, in hand-made cigars, [quot ]rope[quot ] tobacco and freshly picked tobacco leaves from the parish of Manchester in central Jamaica, were compared with locally packaged and imported cigarettes and cigars. Except for chromium and vanadium, which are lower in the imported products, the elemental concentrations of all the brands sold in Jamaica are rather similar. The means for aluminium, cadmium, caesium, cerium, chromium, iron, thorium, uranium, vanadium and zinc for the Manchester material exceed the maximum values of the other tobaccos. The significant concentrations of heavy metals, and especially cadmium, which is about 50 times that of commercial cigarettes, reflect the known high concentrations in the soils in the region. This tobacco is not filtered and the smoke contains 50 of the cadmium. This, and the concentrations of radioactive elements, may indicate an additional health risk compared with commercial cigarettes. A study of three samples of marijuana indicates a similar level of risk from heavy metals

Thermoluminescence dosimetry in the Caribbean

The results of five years of radiation monitoring of 590 radiation workers in Jamaica and an additional 88 in Barbados and The Turks and Caicos Islands show that the annual dose absorbed by Caribbean radiation workers is, with a single exception, well within the internationally accepted limits of 20 mSv per year. There were few cases of relatively high exposures. The dose equivalent of the radiation workers by category agrees with international trends; workers in nuclear medicine receive the highest doses and dental radiologists the lowest. The collective Effective Dose Equivalent has been calculated for each of the monitored populations and certain trends identified. The risk for development of fatal cancers from the occupational doses reported was very low. Consistent monitoring will identify aberrant conditions quickly and help maintain that record