Low-level exposure to lead, blood pressure, and hypertension in a population-based cohort.

Abstract Background Environmental lead exposure is a possible causative factor for increased blood pressure and hypertension, but large studies at low-level exposure are scarce, and results inconsistent. Objective We aimed to examine the effects of environmental exposure to lead in a large population-based sample. Methods We assessed associations between blood lead and systolic/diastolic blood pressure and hypertension in 4452 individuals (46–67 years) living in Malmo, Sweden, in 1991–1994. Blood pressure was measured using a mercury sphygmomanometer after 10 min supine rest. Hypertension was defined as high systolic (≥140 mmHg) or diastolic (≥90 mmHg) blood pressure and/or current use of antihypertensive medication. Blood lead was calculated from lead in erythrocytes and haematocrit. Multivariable associations between blood lead and blood pressure or hypertension were assessed by linear and logistic regression. Two-thirds of the cohort was re-examined 16 years later. Results At baseline, mean blood pressure was 141/87 mmHg, 16% used antihypertensive medication, 63% had hypertension, and mean blood lead was 28 µg/L. Blood lead in the fourth quartile was associated with significantly higher systolic and diastolic blood pressure (point estimates: 1–2 mmHg) and increased prevalence of hypertension (odds ratio: 1.3, 95% confidence interval: 1.1–1.5) versus the other quartiles after adjustment for sex, age, smoking, alcohol, waist circumference, and education. Associations were also significant with blood lead as a continuous variable. Blood lead at baseline, having a half-life of about one month, was not associated with antihypertensive treatment at the 16-year follow-up. Conclusions Low-level lead exposure increases blood pressure and may increase the risk of hypertension

Inductively Coupled Plasma Spectrometry for Speciation Analysis : Development and Applications

In analytical chemistry the main goal is normally to determine the identity and/or concentration of one or more species in a sample. The samples analyzed are often natural samples, containing numerous different species in a complex matrix and the choice of technique for multi-elemental detection is in general inductively coupled plasma spectrometry. The chemical forms of an element can affect many of its characteristics e.g. toxicity, which makes speciation analysis important. Therefore, determination of the identity and quantity of an element is still important, but for many applications measurements of total element concentration provides insufficient information. To be able to perform speciation analysis, separation, identification and/or characterization of the various forms of elements in the sample has to be accomplished. Speciation analysis has been employed in a wide range of disciplines, including for example environmental science, biology and clinical chemistry. This thesis describes work to improve and understand the elemental speciation analysis with liquid chromatography coupled to plasma spectrometry and also highlights the importance and potential of the synergy between atomic spectrometry and molecular mass spectrometry. The combination of the matrix tolerant, robust and very sensitive plasma spectrometry used together with molecular mass spectrometry, which provides structural information and the possibility to identify unknown species, is demonstrated to be a very powerful tool for speciation analysis. In this thesis methods are developed for on-line sample clean-up and pre-concentration coupled to liquid chromatography and plasma spectrometry, which makes handling of small sample volumes easier and also decreases the risk of contamination. The problems associated with organic modifiers in plasma spectrometry are also addressed. Applications of speciation analysis are exemplified by analysis of aluminium-chelated siderophores in field-soil solutions and organic phosphorous species in aquatic sediments. The possibility to analyze un-dissolved samples as slurries with minimal sample preparation is also discussed

Inductively Coupled Plasma Spectrometry for Speciation Analysis : Development and Applications

In analytical chemistry the main goal is normally to determine the identity and/or concentration of one or more species in a sample. The samples analyzed are often natural samples, containing numerous different species in a complex matrix and the choice of technique for multi-elemental detection is in general inductively coupled plasma spectrometry. The chemical forms of an element can affect many of its characteristics e.g. toxicity, which makes speciation analysis important. Therefore, determination of the identity and quantity of an element is still important, but for many applications measurements of total element concentration provides insufficient information. To be able to perform speciation analysis, separation, identification and/or characterization of the various forms of elements in the sample has to be accomplished. Speciation analysis has been employed in a wide range of disciplines, including for example environmental science, biology and clinical chemistry. This thesis describes work to improve and understand the elemental speciation analysis with liquid chromatography coupled to plasma spectrometry and also highlights the importance and potential of the synergy between atomic spectrometry and molecular mass spectrometry. The combination of the matrix tolerant, robust and very sensitive plasma spectrometry used together with molecular mass spectrometry, which provides structural information and the possibility to identify unknown species, is demonstrated to be a very powerful tool for speciation analysis. In this thesis methods are developed for on-line sample clean-up and pre-concentration coupled to liquid chromatography and plasma spectrometry, which makes handling of small sample volumes easier and also decreases the risk of contamination. The problems associated with organic modifiers in plasma spectrometry are also addressed. Applications of speciation analysis are exemplified by analysis of aluminium-chelated siderophores in field-soil solutions and organic phosphorous species in aquatic sediments. The possibility to analyze un-dissolved samples as slurries with minimal sample preparation is also discussed

Inductively Coupled Plasma Spectrometry for Speciation Analysis : Development and Applications

In analytical chemistry the main goal is normally to determine the identity and/or concentration of one or more species in a sample. The samples analyzed are often natural samples, containing numerous different species in a complex matrix and the choice of technique for multi-elemental detection is in general inductively coupled plasma spectrometry. The chemical forms of an element can affect many of its characteristics e.g. toxicity, which makes speciation analysis important. Therefore, determination of the identity and quantity of an element is still important, but for many applications measurements of total element concentration provides insufficient information. To be able to perform speciation analysis, separation, identification and/or characterization of the various forms of elements in the sample has to be accomplished. Speciation analysis has been employed in a wide range of disciplines, including for example environmental science, biology and clinical chemistry. This thesis describes work to improve and understand the elemental speciation analysis with liquid chromatography coupled to plasma spectrometry and also highlights the importance and potential of the synergy between atomic spectrometry and molecular mass spectrometry. The combination of the matrix tolerant, robust and very sensitive plasma spectrometry used together with molecular mass spectrometry, which provides structural information and the possibility to identify unknown species, is demonstrated to be a very powerful tool for speciation analysis. In this thesis methods are developed for on-line sample clean-up and pre-concentration coupled to liquid chromatography and plasma spectrometry, which makes handling of small sample volumes easier and also decreases the risk of contamination. The problems associated with organic modifiers in plasma spectrometry are also addressed. Applications of speciation analysis are exemplified by analysis of aluminium-chelated siderophores in field-soil solutions and organic phosphorous species in aquatic sediments. The possibility to analyze un-dissolved samples as slurries with minimal sample preparation is also discussed

Is cadmium a risk factor for breast cancer - Results from a nested case-control study using data from the malmö diet and cancer study

Background: Some studies have shown that cadmium (Cd) is associated with breast cancer risk. One hypothesis is that Cd has estrogen-like properties. This case-control study investigated the association between breast cancer risk and blood Cd (BCd) levels. Methods: All breast cancers in the Malmö Diet and Cancer cohort were identified through linkage to the Swedish Cancer Registry, baseline (1991-1996) through 2014. Two controls per case were selected from the same cohort. BCd was analyzed at baseline. Associations were analyzed using logistic regression. Results: Mean BCd was 0.51 mg/L among 1, 274 cases and 0.46 among 2, 572 controls. There was an overall increased risk of breast cancer [OR, 1.18; 95% confidence interval (CI), 1.05-1.36] per mg/L of BCd. An increased risk was, however, only found at high BCd [OR, 1.34 (95% CI, 1.05-1.73)] for BCd more than 1.20 mg/L. The group with the highest BCd was mainly smokers. A spline indicated that at BCd less than 1.0 mg/L, the OR was not increased. The association with BCd was stronger in current smokers and at body mass index (BMI) above 25, while no modification due to receptor status was found. Conclusions: The results indicated increased risk of breast cancer only for high Cd exposure, which occurred mainly among smokers. This made it difficult to disentangle the effects of smoking and Cd, despite inclusion of smoking habits in the models. Impact: This study provides support for reducing Cd exposure through smoking cessation and dietary choice. On the population level, preventive measures against Cd pollution are warranted

Cadmium exposure and incidence of diabetes mellitus--results from the Malmö Diet and Cancer study.

Cadmium is a pollutant with multiple adverse health effects: renal dysfunction, osteoporosis and fractures, cancer, and probably cardiovascular disease. Some studies have reported associations between cadmium and impaired fasting glucose and diabetes. However, this relationship is controversial and there is a lack of longitudinal studies.To examine prospectively whether cadmium in blood is associated with incidence of diabetes mellitus.The study population consists of 4585 subjects without history of diabetes (aged 46 to 67 years, 60% women), who participated in the Malmö Diet and Cancer study during 1991-1994. Blood cadmium levels were estimated from hematocrit and cadmium concentrations in erythrocytes. Incident cases of diabetes were identified from national and local diabetes registers.Cadmium concentrations in blood were not associated with blood glucose and insulin levels at the baseline examination. However, cadmium was positively associated with HbA1c in former smokers and current smokers. During a mean follow-up of 15.2 ± 4.2 years, 622 (299 men and 323 women) were diagnosed with new-onset of diabetes. The incidence of diabetes was not significantly associated with blood cadmium level at baseline, neither in men or women. The hazard ratio (4th vs 1st quartile) was 1.11 (95% confidence interval 0.82-1.49), when adjusted for potential confounders.Elevated blood cadmium levels are not associated with increased incidence of diabetes. The positive association between HbA1c and blood cadmium levels has a likely explanation in mechanisms related to erythrocyte turnover and smoking

Cadmium exposure and atherosclerotic carotid plaques -Results from the Malmö diet and Cancer study.

Epidemiological studies indicate that cadmium exposure through diet and smoking is associated with increased risk of cardiovascular disease. There are few data on the relationship between cadmium and plaques, the hallmark of underlying atherosclerotic disease

Blood lead levels and risk of atherosclerosis in the carotid artery : Results from a swedish cohort

BACKGROUND: Lead exposure has been associated with increased incidence of adverse clinical cardiovascular outcomes. Atherosclerosis has been suggested as one of the underlying mechanisms, and findings from experimental studies support this, but human data are scarce. OBJECTIVES: Our objective was to determine the association between environmental lead exposure based on blood lead (B-Pb) concentrations and the prevalence of atherosclerotic plaque in the carotid artery. METHODS: We used cross-sectional data from the Malmö Diet and Cancer Study cardiovascular cohort (MDCS-CC; recruitment in 1991–1994) covering 4,172 middle-aged men and women. B-Pb at baseline, measured by inductively coupled plasma mass spectrometry, was used as the exposure biomarker. The presence of atherosclerotic plaque in the carotid artery was determined by B-mode ultrasonography. We used logistic regression to estimate odds ratios (ORs) for prevalence of plaque in the carotid artery according to B-Pb quartiles. RESULTS: The median B-Pb was 25 lg=L (range: 1.5–258), and 36% of the cohort had any atherosclerotic plaque. After controlling for confounders and known cardiovascular risk factors, the OR for prevalence of plaque in the highest quartile (Q4) of B-Pb compared with the lowest quartile (Q1) was 1.35 (95% CI: 1.09, 1.66) in the total group, 1.58 (95% CI: 1.20, 2.08) among women, and 1.18 (95% CI: 0.83, 1.69) among men. Among women, associations were limited to those who were postmenopausal [OR for Q4 vs. Q1 = 1.72 (95% CI: 1.26, 2.34) vs. OR = 0.96 (95% CI: 0.49, 1.89 in premenopausal women)]. Associations were weak and nonsignificant in never-smokers [OR for Q4 vs. Q1 = 1.14 (95% CI: 0.81, 1.61)]. DISCUSSION: Our study shows an association between B-Pb concentrations and occurrence of atherosclerotic plaque in the carotid artery, adding evidence for an underlying pro-atherogenic role of lead in cardiovascular disease. Associations appeared to be limited to postmenopausal (vs. premeno-pausal) women. https://doi.org/10.1289/EHP5057

Cadmium exposure is associated with soluble urokinase plasminogen activator receptor, a circulating marker of inflammation and future cardiovascular disease

Background Diet and smoking are the main sources of cadmium exposure in the general population. Cadmium increases the risk of cardiovascular diseases, and experimental studies show that it induces inflammation. Blood cadmium levels are associated with macrophages in human atherosclerotic plaques. Soluble urokinase-type plasminogen activator receptor (suPAR) is an emerging biomarker for cardiovascular events related to inflammation and atherosclerotic plaques. The aim was to examine whether blood cadmium levels are associated with circulating suPAR and other markers of inflammation. Methods A population sample of 4648 Swedish middle-aged women and men was examined cross-sectionally in 1991–1994. Plasma suPAR was assessed by ELISA, leukocytes were measured by standard methods, and blood cadmium was analysed by inductively coupled plasma mass spectrometry. Prevalent cardiovascular disease, ultrasound-assessed carotid plaque occurrence, and several possible confounding factors were recorded. Results After full adjustment for risk factors and confounding variables, a 3-fold increase in blood cadmium was associated with an 10.9% increase in suPAR concentration (p<0.001). In never-smokers, a 3-fold increase in blood cadmium was associated with a 3.7% increase in suPAR concentration (p<0.01) after full adjustment. Blood cadmium was not associated with C-reactive protein, white blood cell count and Lp-PLA2 but with neutrophil/lymphocyte ratio in one of two statistical models. Conclusions Exposure to cadmium was associated with increased plasma suPAR in the general population, independently of smoking and cardiovascular disease. These results imply that cadmium is a possible cause for raised levels of this inflammatory marker