RESUMO
Coffee consumption is associated with reduced risk of conditions that share low-grade inflammation as their physiopathological basis. We therefore summarized the effects of coffee or coffee components on serum levels of inflammatory markers. Clinical trials assessing the effect of coffee, caffeine or other coffee components on inflammatory markers were searched without restriction to publication date. Fifteen studies (8 involving coffee and 7 caffeine) were included. Increased adiponectin levels were found in four of seven trials comparing filtered coffee/caffeinated coffee with placebo or comparing its levels at baseline and after consumption of medium or dark roasted coffee, but no change was seen in caffeine trials. None of the five studies assessing the effects of coffee found changes in C-reactive protein (CPR), but one out of three trials found decreased CPR levels in response to caffeine. Interleukin (IL)-6 was increased by caffeinated coffee compared with placebo in one of four coffee trials, and by caffeine in three out of five studies. Caffeine increased IL-10 levels in two of three trials. These data suggest a predominant anti-inflammatory action of coffee but not of caffeine consumption. Moreover, the proinflammatory and anti-inflammatory responses to caffeine point to its complex effects on the inflammatory response.
Assuntos
Biomarcadores/sangue , Cafeína/administração & dosagem , Café , Inflamação/sangue , Adulto , Anti-Inflamatórios , Proteína C-Reativa/análise , Cafeína/efeitos adversos , Café/efeitos adversos , Ensaios Clínicos Controlados como Assunto , Citocinas/sangue , Feminino , Humanos , MEDLINE , Masculino , Pessoa de Meia-IdadeRESUMO
AIM: We studied the effect on neurodevelopment of infants who are exposed to thimerosal in tetanus-diphtheria (Td) vaccines during pregnancy. METHODS: We compared Gesell Developmental Schedules (GDS) of exclusive breastfed infants at 6 months born to mothers who received Td (1 to 3 doses) against those who were born to mothers who did not take such vaccines. RESULTS: Compared with the group of infants not exposed to ethylmercury in utero, the infants of exposed mothers showed no significant difference in neurodevelopment delays. Although there was a significant correlation between hair-Hg of mothers and hair-Hg of neonates (Spearman r = 0.353; p = 0.0011), there was no significant correlation between the level of in utero exposure to ethylmercury in Td vaccines and neonate's hair-Hg concentrations (Spearman r = 0.060; p = 0.5922). However, regression analysis showed that GDS at 6 months was significantly associated with total mercury concentration of neonate's hair but was not sensitive to the number of vaccines taken by the mother. CONCLUSION: Early neurodevelopment of exclusively breastfed infants is sensitive to in utero exposure to mercury, but maternal thimerosal exposure in tetanus-diphtheria vaccines per se cannot portend clinical neurodevelopment delays measured by GDS at 6 months.
Assuntos
Deficiências do Desenvolvimento/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal , Conservantes Farmacêuticos/efeitos adversos , Timerosal/efeitos adversos , Adolescente , Adulto , Aleitamento Materno , Toxoide Diftérico/efeitos adversos , Feminino , Cabelo/química , Humanos , Lactente , Pessoa de Meia-Idade , Testes Neuropsicológicos , Gravidez , Análise de Regressão , Toxoide Tetânico/efeitos adversos , Timerosal/análise , Adulto JovemRESUMO
The population living along the riverbanks of the Amazon basin depends heavily on fish for nutritional support. Mono-methyl-mercury (MMHg) concentrates in fish, which can contaminate humans, the risk depending not only on fish MMHg concentration but also on the amount of fish consumed. We sampled nine locations of the Rio Negro basin, differing in water pH, Hg concentrations, and dissolved organic carbon (DOC), and determined total Hg from 951 fish samples of species representative of the food web: herbivorous, detritivorous, omnivorous, and piscivorous. Mercury concentrations varied widely in all species but showed a trend that depended on fish feeding strategies. The highest mean concentration was found in the piscivorous species (688.90 ng/g(-1)), followed by omnivorous (190.30 ng/g(-1)), detritivorous (136.04 ng/g(-1)), and herbivorous (70.39 ng/g(-1)). Fish Hg concentrations exceeding current safe limits (500 ng/g(-1)) for human consumption were found mainly in the piscivorous species (60%). Significant positive correlation between fish weight and Hg concentration was seen for the piscivorous Serrasalmus spp. (n = 326; r = 0.3977; p < 0.0001), Cichla spp. (n = 125; r = 0.4600; p < 0.0001), and Pimelodus spp. (n = 12; r = 0.8299; p = 0.0008), known locally as Piranha, Tucunaré, and Mandi, respectively. However, a negative correlation was seen for non-piscivorous Potamorhina latior (n = 30; r -0.3763; p = 0.0404) and Leporinus spp. (n = 44; r = -3987; p = 0.0073), known as Branquinha (detritivorous) and Aracu (omnivorous). Fish-Hg concentrations in the acidic waters (pH range, 4.09-6.31) of the Rio Negro habitat, with its wide gradient of Hg concentrations (3.4-11.9 microg/L(-1)) and DOC (1.85-15.3 mg/L(-1))--but no history of gold mining activity-are comparable to other Amazonian rivers. Opportunity fish catches in the Rio Negro habitat show high muscle-Hg derived from natural sources, but no systematic association with site-dependent geochemistry.
Assuntos
Dieta , Peixes , Cadeia Alimentar , Mercúrio/farmacocinética , Poluentes da Água/farmacocinética , Animais , Brasil , Carbono/análise , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Mercúrio/análise , Clima Tropical , Poluentes da Água/análiseRESUMO
Human mercury contamination can be monitored through hair analysis of mercury's inorganic and organic form as methylmercury (Me-Hg). Hair total mercury and Me-Hg were studied in a Negro River fish-eating population in relation to age, gender, and body mass index (BMI). This riverbank population eats fish at least twice a day and is exposed to high levels of Me-Hg. Total mercury ranged from 1.51 microg/g to 59.01 microg/g, with only 21% of the sampled population having Hg concentration of less than 10 microg/g hair. The mean percentage of Me-Hg was 71.3% (range 34% to 100%) of the total mercury in hair. No statistically significant differences were found in regard to age groups (children and adults) or BMI. However, women had significantly lower total mercury in hair than men, but the percentage of Me-Hg was not significantly different. Women in fertile age (15-40 years) had hair total mercury ranging from 1.65-32.63 microg/g, and 65% in this subgroup had hair mercury above 10 microg/g hair. The percentage of Me-Hg concentration in hair of this freshwater, fish-eating population is comparable to populations eating ocean fish from different parts of the world and does not seem to be affected by age, gender, and BMI.
Assuntos
Monitoramento Ambiental , Peixes , Contaminação de Alimentos , Cabelo/química , Mercúrio/química , Adolescente , Adulto , Fatores Etários , Idoso , Animais , Índice de Massa Corporal , Brasil , Criança , Dieta , Exposição Ambiental , Feminino , Humanos , Masculino , Mercúrio/análise , Pessoa de Meia-Idade , Fatores SexuaisRESUMO
Umbilical cord and venous blood samples were collected at the time of delivery from 52 mothers living in urban and rural areas of the Atoya River basin, Nicaragua. In a subsample of 24 mothers that delivered by Cesarean section, abdominal adipose tissue samples were also collected, as was breast milk later in lactation. Cord and venous blood sera were analyzed for 13 organochlorine pesticides: 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (pp'-DDT); 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (pp'-DDE); pp'-dichlorophenyldichlorodiene (pp'-DDD); alpha-hexachlorocyclohexane (alpha-HCH); beta-hexachlorocyclohexane (beta-HCH); gamma-hexachlorocyclohexane (gamma-HCH); delta-hexachlorocyclohexane (delta-HCH); toxaphene; dieldrin; endrin; aldrin; heptachlor; and heptachlor epoxide. In venous blood only pp'-DDE (100% of samples), pp'-DDT (1.92%), dieldrin (15.38%), heptachlor (15.38%), gamma-HCH (7.69%), beta-HCH (11.53%), and delta-HCH (1.92%) were found, whereas in cord blood only pp'-DDE (100%), pp'-DDT (3.84%), dieldrin (19.23%), and heptachlor (9.16%), were found. The persistent DDT metabolite pp'-DDE, present in all samples of blood serum, adipose tissue, and breast milk, was studied in relation to maternal characteristics such as body mass index (BMI), age, lactation experience, and fetal pesticide acquisition. Mean venous (7.12 microg/g) and cord (6.39 microg/g) pp'-DDE concentrations were not significantly different but were significantly correlated. pp'-DDE in maternal adipose tissue was positively correlated with pp'-DDE in cord blood (P=0.0001) and breast milk (P<0.0001) and marginally correlated with changes in BMI (r=-0.03088; P=0.06). There was a higher proportion of samples (58%) with a greater concentration of DDE in venous than in cord blood. Although DDE accumulation may be less during fetal development than during breast feeding, exposure during embryogenesis may be more important than during the postnatal period.
Assuntos
Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/sangue , Sangue Fetal/química , Inseticidas/análise , Inseticidas/sangue , Leite Humano/química , Tecido Adiposo/química , Adolescente , Adulto , Índice de Massa Corporal , Feminino , Número de Gestações , Humanos , Troca Materno-Fetal , Nicarágua , Gravidez , Sensibilidade e Especificidade , VeiasRESUMO
The effects of intrauterine device (IUD) on maternal copper (Cu) metabolism during breastfeeding was studied in 95 volunteer mothers who chose to use non-hormonal contraceptive methods. They were divided into two groups that were inserted with the IUD-Cu 380A (n = 33), IUD-Cu 200B (n = 29), and a third group that did not use any IUDs served as control (n = 33). Endometrial biopsies, blood, and milk samples were collected before (at 10 weeks postpartum) and 6 weeks after insertion of device for the determination of metabolites associated with copper metabolism, namely, serum ceruloplasmin, and copper concentrations in breast milk and endometrium. Endometrial copper concentration increased in women using IUDs, but was statistically significant (p = 0.001) only in the IUD-Cu 380A group. The increase in endometrial copper concentration did not affect serum ceruloplasmin or milk copper concentrations.
Assuntos
Cobre/metabolismo , Dispositivos Intrauterinos de Cobre/efeitos adversos , Lactação , Adulto , Biópsia , Ceruloplasmina/análise , Ceruloplasmina/metabolismo , Cobre/análise , Cobre/sangue , Endométrio/química , Feminino , Humanos , Leite Humano/química , Leite Humano/metabolismoRESUMO
This study of 230 Brazilian mothers examined the associations of several sociodemographic variables, maternal attitudes and perceptions with intended breast feeding duration. The usual relationships of sociodemographic variables such as mother's age, education, smoking, parity and infant birth weight with intended breast feeding duration were not found. However, mother's intentions were related to gender role attitudes with both the least and the most traditional women intending to breast feed longer than women with moderately traditional gender role attitudes. Mother's attitude toward breast feeding, help with household tasks, and the attitudes of friends and relatives toward breast feeding were also very significantly related to intended breast feeding duration. Women who did not work outside the home intended to breast feed significantly longer than those who were employed.
Assuntos
Atitude , Aleitamento Materno , Identidade de Gênero , Adolescente , Adulto , Brasil , Aleitamento Materno/psicologia , Emprego , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Fatores SocioeconômicosRESUMO
OBJECTIVES: To study the effects of oral contraceptives on magnesium metabolism of lactating mothers. METHODS: Serum and breast-milk magnesium were measured in three groups of mothers that were using combination pill (12), mini-pill (21), and a control group (21). RESULTS: There was no significant effect of oral contraceptives on breast-milk magnesium. CONCLUSIONS: The use of oral contraceptives such as the combination pill and mini-pill does not seem to affect the secretion of magnesium in breast milk.
Assuntos
Anticoncepcionais Orais Combinados/efeitos adversos , Etinilestradiol/efeitos adversos , Levanogestrel/efeitos adversos , Magnésio/análise , Leite Humano/química , Leite Humano/efeitos dos fármacos , Noretindrona/efeitos adversos , Adulto , Fatores de Confusão Epidemiológicos , Características da Família , Feminino , Humanos , Magnésio/sangue , Idade Materna , Leite Humano/metabolismo , Classe Social , Fatores de TempoRESUMO
Breast-milk samples from 101 mothers from the basin of Rio Aloya, Nicaragua, were collected on two occasions within the first trimester of lactation. Milk samples were analyzed for 13 organochlorine pesticides: (1) p,p'-dichlorophenyldichloroethylene; (2) p,p'-dichlorophenyltrichloroethane; (3) p,p'-dichlorophenyldichlorodiene; (4) alpha-hexachlorocyclohexane; (5) beta-hexachlorocyclohexane; (6) gamma-hexachlorocyclohexane; (7) delta-hexachlorocyclohexane; (8) toxaphene; (9) dieldrin; (10) endrin; (11) aldrin; (12) heptachlor; and (13) heptachlor-epoxide. Organochlorines of the dichlorodiphenylethane class (i.e., p,p'-dichlorodiphenylethane and p,p'-dichlorodiphenylethane) were found in all samples and at the highest mean concentrations observed in the study. Chemicals in the hexachlorocyclohexane family (i.e., alpha- and delta-hexachlocyclohexane) were not found at all (0%), and the other hexachlorocyclohexane compounds (i.e., beta > gamma) were found in less than 6% of the samples. Twenty percent or less of the sample contained chlorInated cyclodienes (i.e., dieldrin > endrin > heptachlor-epoxide > heptachlor). No measurable concentrations of alpha-hexachlorocyclohexane, aldrin, p,p'-dichlorophenyldichlorodiene, and toxaphene were found in the breast milk samples. Analysis of variance demonstrated that only the concentration of p,p'-dichlorophenyldichloroethylene p,p'-dichlorophenyltrichloroethane, and endrin were affected significantly by maternal age. Overall, with the exception of p,p'-chlorophenyldichloroethylene, and p,p'-dichlorophenyltrichloroethane, the mean concentrations of the analyzed pesticides were low. Total p,p'-dichlorophenyltrichloroethane concentrations that exceeded the allowed daily intake set by the World Health Organisation were found in 5.9% of the samples.
Assuntos
Exposição Ambiental/análise , Hidrocarbonetos Clorados , Inseticidas/análise , Leite Humano/efeitos dos fármacos , Mães , Agricultura , Exposição Ambiental/efeitos adversos , Feminino , Cadeia Alimentar , Humanos , Lactente , Recém-Nascido , Inseticidas/efeitos adversos , Nicarágua , GravidezRESUMO
Reported concentrations for magnesium in breast milk vary over a wide range (15 to 64 mg/L) with a median value of 31 mg/L and 75% of reported mean concentrations below 35 mg/L. Constitutional variables such as adolescent motherhood, gestation length, maternal undernutrition, metabolic disorders (diabetes, galactosemia), race, stage of lactation, sampling techniques (foremilk and hindmilk), as well as environmental variables such as socio-cultural diversity, smoking habits, dietary calcium and magnesium (including supplementation), vegetarianism, calciotropic agents (immunoreactive calcitonin, vitamin D), medication (hormonal contraceptives, magnesium sulfate) are critically reviewed in relation to changes in milk magnesium concentrations. Magnesium secretion into breast milk does not seem to be affected by the studied variables.
Assuntos
Magnésio/análise , Leite Humano/química , Meio Ambiente , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Lactação , Magnésio/administração & dosagem , Magnésio/metabolismo , Necessidades Nutricionais , Valores de ReferênciaRESUMO
The reported concentrations of iron and copper in breast milk show a wide variation. Research published over the past 50 y has reported median values of 0.47 and 0.32 mg/L for iron and copper, respectively. The levels of both metals decrease with the progress of lactation. The calculated iron-to-copper ratio of reported means differs from 0.25 to 6.29 (median = 1.18). Maternal constitutional variables such as undernutrition, iron and copper body reserves, stage of lactation, adolescent motherhood, gestation length, and infection and environmental variables such as iron and copper dietary intake, in addition to supplementation, smoking, vegetarianism, and prolonged use of hormonal contraceptives before and during lactation did not consistently affect the concentrations of iron and copper in breast milk. Extreme cases of either low or high levels of body metal availability or altered metabolism due to chelating therapy or illnesses such as Wilson's disease and infections did not affect metal transfer from blood serum to breast milk. There is no clinical or scientific support for the need of extra iron or copper, besides the quantities provided by milk in the full-term breast-fed infant, at least during the first 6 mo.
Assuntos
Cobre/análise , Ferro/análise , Leite Humano/química , Anticoncepcionais Orais , Dieta , Feminino , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Recém-Nascido Prematuro , LactaçãoAssuntos
Cálcio/análise , Leite Humano/química , Fósforo/análise , Feminino , Humanos , Período Pós-Parto , Fatores de TempoRESUMO
Selenium concentration was measured in the breast milk of 30 mothers at different stages of lactation and various body mass indices (BMI). For a maternal mean selenium intake meeting 100% of the Recommended Daily Allowance, mean milk selenium concentration was 14.06 ng/mL (range: 10.0-24.7 ng/mL). No significant correlation was found between the concentration of milk selenium with the stage of lactation, BMI, or dietary selenium intake.
Assuntos
Dieta , Leite Humano/química , Selênio/análise , Adulto , Índice de Massa Corporal , Feminino , Humanos , Mobilização Lipídica , Período Pós-Parto , GravidezRESUMO
OBJECTIVE: To determine the effects of oral contraceptive (OC) treatment on maternal iron and copper metabolism during lactation. DESIGN: Observational study. SETTING: Private and public clinics in Brazil. PATIENT(S): Lactating mothers attending the family planning clinic of the University of Brasilia. INTERVENTION(S): The OCs used were a combination pill (0.15 mg of levonorgestrel and 0.03 mg of ethinyl estradiol) and a minipill (0.35 mg of norethidrone). Blood and breast milk samples were collected before and after a measured period of OC treatment. MAIN OUTCOME MEASURE(S): Iron and copper concentrations were studied in the serum and breast milk of 54 breast-feeding mothers who had been advised by their physicians to use an OC, and in a control group. RESULT(S): Regression analysis was performed using a model that took into consideration socioeconomic status, number of children, duration of previous lactation, type of OC, length of treatment, and age. Repeated measurements (before and after OC treatment) showed that only copper concentrations in breast milk were significantly affected by stage of lactation. During the study period, which varied from 2-15 weeks, the decline in iron concentrations in breast milk was negligible, whereas copper concentrations decreased by 50%. CONCLUSION(S): The use of OCs does not appear to affect significantly the secretion of iron and copper in breast milk during the first 6 months of lactation.
PIP: This study examines the effects of oral contraceptive (OC) treatment on maternal iron and copper metabolism during lactation. The sample included lactating mothers attending the family planning clinic at the University of Brasilia. Participants were divided into 3 groups: 1) mothers who were taking combination pills (0.15 mg levonorgestrel and 0.03 mg ethinyl estradiol); 2) those who were taking minipills (0.35 mg norethindrone); and 3) a control group. Blood and breast milk samples were collected before and after a measured period of OC treatment. Results showed no significant effects of OC use on either iron or copper concentrations in serum during lactation. However, copper concentrations were significantly affected with the stage of lactation (iron, P = 0.9619; copper, P = 0.0002) as reflected in the multivariate model analysis. Therefore, the use of OCs does not appear to affect significantly the secretion of iron and copper in breast milk during the first 6 months of lactation.
Assuntos
Anticoncepcionais Orais , Cobre/análise , Ferro/análise , Leite Humano/química , Adolescente , Adulto , Anticoncepcionais Orais Combinados , Cobre/sangue , Feminino , Humanos , Ferro/sangue , LactaçãoRESUMO
OBJECTIVE: Oral contraceptives (OC) are the most efficient method of contraception and it is the most prescribed by doctors in developing countries. Therefore we studied the effects of combination pill and mini-pill on calcium and phosphorus in milk of breast-feeding mothers at different stages of lactation. METHODS: Fifty-four breast-feeding mothers made up three study groups: 33 mothers who had been advised by their doctors to use either combination pill (12), or mini-pill (21), as well as a control group of 21 mothers that used no hormonal contraceptives. All mothers completed a questionnaire and provided samples of milk before and after a measured period of observation. Mean duration of study was 76, 120, and 101 days, respectively for users of mini-pill, combination pill, and controls. Determination of calcium and phosphorus was done by inductively coupled plasma-atomic absorption spectrometry. RESULTS: Overall the decrease in milk concentrations of phosphorus (6%) and calcium (26.3%) during the study period was not influenced by OC treatment. Regression analyses which took into consideration length of treatment, socioeconomic status, number of children, duration of previous lactation, type of contraceptive, and age of mothers and repeated measurements (before and after OC) showed that milk calcium was significantly affected by stage of lactation (p=0.0013). CONCLUSION: The use of hormonal contraceptive such as the combination pill (levonorgestrel 0.15 mg+ethynilestradiol 0.03 mg) and mini-pill (norethindone 0.35 mg) does not seem to affect the secretion of calcium and phosphorus in milk of mothers.
PIP: This article is based on a study of the effects of oral contraceptives (OCs) on the concentration of calcium and phosphorus in breast milk among 54 lactating Brazilian women. Confounding constitutional variables were considered which include maternal age, previous lactation, length of breast-feeding, and variables associated with contraception, such as type and length of use. The subjects were divided into 3 groups: 12 using combination pills, 21 using mini-pills, and a control group of 21 mothers that used no hormonal contraceptives. Milk was sampled before and after a measured period of observation. The mean durations of study were 76, 120, and 101 days, respectively, for users of mini-pills, combination pills, and controls. The determination of calcium and phosphorous was done by inductively coupled plasma-atomic absorption spectrometry. The results indicate that a mean stage of lactation at start of treatment for the 3 groups ranged from 2.5 to 4 months. Both calcium and phosphorous declined in concentration with time, confounded with OC treatment. There was no significant difference for calcium concentration due to OC treatment, only stage of lactation, per se, was a significant source of variation for calcium concentration. As lactation progressed, the calcium and phosphorous concentration decreased for all mothers. Therefore, short-term use of OCs containing estrogen do not affect calcium and phosphorous concentrations in breast milk.
Assuntos
Cálcio/análise , Anticoncepcionais Orais/efeitos adversos , Lactação , Leite Humano/química , Fósforo/análise , Adolescente , Adulto , Anticoncepcionais Orais Combinados/efeitos adversos , Etinilestradiol/administração & dosagem , Etinilestradiol/efeitos adversos , Feminino , Humanos , Levanogestrel/administração & dosagem , Levanogestrel/efeitos adversos , Noretindrona/administração & dosagem , Noretindrona/efeitos adversos , Análise de RegressãoRESUMO
Hair mercury concentration, as an indicator of mercury body load, was studied in 251 samples of indigenous women and children living in selected areas of the Amazonian region. The mothers or women of child-bearing age, either non-Indians or Indians, and their children were sampled along the Madeira River and in the Kayapó reservation (Fresco River), respectively. Among the sampled individuals there were mothers with infants less than 2 years old. Total mercury in hair was determined by cold vapor atomic absorption spectrometry after alkaline digestion. The distribution of hair mercury concentration greater than 10 microg/g occurred in 67.4% of non-Indian women and 25% of Indian women; overall only 1% of non-Indian women had concentrations of hair mercury above 50 microg/g. In women of child-bearing age, the median and range of hair mercury concentration was 14.08 microg/g, and 0.8-94.7 microg/g for non-Indians, and 8.30 microg/g, and 0.8-13.3 microg/g for Indians. The correlation between maternal hair mercury and mercury in hair of infants (less than 2 years of age) still breast-feeding, was statistically significant only for non-Indians (r = 0.555 p < 0. 001). The correlation between length of breast-feeding and mercury concentration in infant's hair was significant for Indian children (r = 0.512; p = 0.029) but not for non-Indian children (r = 0.025; p = 0.832). A subsampling of 30 mothers had segmented hair analysis that showed a mean decrease of 20% in body burden during pregnancy, thus indicating the extent of placental transference of mercury to fetuses.
Assuntos
Exposição Ambiental/análise , Cabelo/química , Indígenas Sul-Americanos , Mercúrio/análise , Adulto , Carga Corporal (Radioterapia) , Brasil , Aleitamento Materno , Feminino , Humanos , Lactente , Mercúrio/metabolismo , Pessoa de Meia-Idade , Gravidez/metabolismo , Trimestres da Gravidez , Valores de ReferênciaRESUMO
Mercury pollution, due to gold mining has spread through the Amazon ecosystem reaching the food chain and affecting the indigenous people of the region. We studied the mercury contamination of 47 mothers and infants and the role of breast feeding in indices of mercury body burden in both groups, by measuring hair and milk Hg levels. Total mercury concentration of breast milk ranged from 0.0 to 24.8 (5.85, 5.2 S.D.) ng/g. Calculated levels of mercury exposure of breast fed babies indicated that 53% were above tolerable daily intakes (0.5 µg/kg body weight) recommended for adults by WHO. Mercury concentration in maternal hair was higher than in hair from breast-fed babies. Correlation analysis showed that mercury hair concentration in infants was significantly affected by maternal mercury contamination during pregnancy, but not during the post-natal breast-feeding period. The mercury concentration in milk was not significantly correlated with maternal or infant's hair Hg. A statistically significant correlation was found only between maternal and infant's hair mercury concentration (r=0.675; P=0.0001).
RESUMO
Samples of 7 species of piscivorous, omnivorous, and herbivorous fish caught at 12 different sites on the Madeira River, Amazon Basin, were analyzed for selenium and mercury. Selenium was determined by anodic stripping voltammetry and mercury by cold vapor atomic absorption spectrophotometry. The means for selenium concentrations ranged from 0.49 to 3.11 nmol/g and for mercury from 0.41 to 6.66 nmol/g depending on the fish species. The molar ratios of Hg:Se increased according to the fish trophic level. Piscivorous species had the highest mean ratio (4.0) and herbivorous species the lowest (0.9). There was a positive and statistically significant correlation between selenium and mercury concentrations for the herbivorous species (r = 0.716; p = 0.0088) not seen for omnivororus and piscivorous species (r = -0.2032; p = 0.3407). These findings are significant for the fish-eating population of the Madeira River because the ingestion of mercury would always be in excess of selenium.