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1.
Toxicol Rep ; 5: 390-395, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854609

RESUMO

Prenatal vitamins are often consumed daily during gestation and postnatally for up to 18-24 months with the belief that supplementation achieves better outcomes. Detrimental effects of gestational exposure to adverse chemical agents are gathering increasing attention. This study was designed to assess toxic element contamination in prenatal supplements. Twenty-six commonly used prenatal vitamin brands including one prescription brand were collected from Canadian health-food outlets and pharmacies, and tested for toxic element contamination. Results were compared to established endpoints. All samples contained Lead with average amounts being (0.535 µgm), 20/51 samples exceeded established standards for lead toxicity (0.50 µgm/day), with one sample yielding 4. µgm/day. Three samples registered inorganic arsenic levels above acceptable limits. Cadmium levels did not exceed current standards. Toxic elements such as Aluminum, Nickel, Titanium and Thallium were detected in all samples. Cumulative intake of prenatal supplement over many months may constitute a significant source of toxic element exposure to the mother and offspring. With several samples exceeding known standards for gestational toxic element exposure, guidelines for routine monitoring and reporting are required. In keeping with recommendations from the International Federation of Obstetrics and Gynecology, industry regulation would be welcomed to protect expectant mothers and their vulnerable offspring.

2.
Scientifica (Cairo) ; 2017: 4179326, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29093983

RESUMO

The scientific literature provides extensive evidence of widespread magnesium deficiency and the potential need for magnesium repletion in diverse medical conditions. Magnesium is an essential element required as a cofactor for over 300 enzymatic reactions and is thus necessary for the biochemical functioning of numerous metabolic pathways. Inadequate magnesium status may impair biochemical processes dependent on sufficiency of this element. Emerging evidence confirms that nearly two-thirds of the population in the western world is not achieving the recommended daily allowance for magnesium, a deficiency problem contributing to various health conditions. This review assesses available medical and scientific literature on health issues related to magnesium. A traditional integrated review format was utilized for this study. Level I evidence supports the use of magnesium in the prevention and treatment of many common health conditions including migraine headache, metabolic syndrome, diabetes, hyperlipidemia, asthma, premenstrual syndrome, preeclampsia, and various cardiac arrhythmias. Magnesium may also be considered for prevention of renal calculi and cataract formation, as an adjunct or treatment for depression, and as a therapeutic intervention for many other health-related disorders. In clinical practice, optimizing magnesium status through diet and supplementation appears to be a safe, useful, and well-documented therapy for several medical conditions.

3.
Biomed Res Int ; 2017: 3676089, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28373979

RESUMO

Commonly used as flame retardants, polybrominated diphenyl ethers (PBDEs) are routinely detected in the environment, animals, and humans. Although these persistent organic pollutants are increasingly recognized as having serious health implications, particularly for children, this is the first study, to our knowledge, to investigate an intervention for human elimination of bioaccumulated PBDEs. Objectives. To determine the efficacy of blood, urine, and perspiration as PBDE biomonitoring mediums; assess excretion of five common PBDE congeners (28, 47, 99, 100, and 153) in urine and perspiration; and explore the potential of induced sweating for decreasing bioaccumulated PBDEs. Results. PBDE congeners were not found in urine samples; findings focus on blood and perspiration. 80% of participants tested positive in one or more body fluids for PBDE 28, 100% for PBDE 47, 95% for PBDE 99, and 90% for PBDE 100 and PBDE 153. Induced perspiration facilitated excretion of the five congeners, with different rates of excretion for different congeners. Conclusion. Blood testing provides only a partial understanding of human PBDE bioaccumulation; testing of both blood and perspiration provides a better understanding. This study provides important baseline evidence for regular induced perspiration as a potential means for therapeutic PBDE elimination. Fetotoxic and reproductive effects of PBDE exposure highlight the importance of further detoxification research.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/isolamento & purificação , Retardadores de Chama/efeitos adversos , Éteres Difenil Halogenados/efeitos adversos , Poluentes Ambientais/sangue , Poluentes Ambientais/urina , Feminino , Éteres Difenil Halogenados/sangue , Éteres Difenil Halogenados/urina , Humanos , Masculino , Pessoa de Meia-Idade , Suor/química
4.
Toxicol Mech Methods ; 27(7): 477-500, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28446067

RESUMO

BACKGROUND: Recent evidence highlights the reality of unprecedented human exposure to toxic chemical agents found throughout our environment - in our food and water supply, in the air we breathe, in the products we apply to our skin, in the medical and dental materials placed into our bodies, and even within the confines of the womb. With biomonitoring confirming the widespread bioaccumulation of myriad toxicants among population groups, expanding research continues to explore the pathobiological impact of these agents on human metabolism. METHODS: This review was prepared by assessing available medical and scientific literature from Medline as well as by reviewing several books, toxicology journals, government publications, and conference proceedings. The format of a traditional integrated review was chosen. RESULTS: Toxicant exposure and accrual has been linked to numerous biochemical and pathophysiological mechanisms of harm. Some toxicants effect metabolic disruption via multiple mechanisms. CONCLUSIONS: As a primary causative determinant of chronic disease, toxicant exposures induce metabolic disruption in myriad ways, which consequently result in varied clinical manifestations, which are then categorized by health providers into innumerable diagnoses. Chemical disruption of human metabolism has become an etiological determinant of much illness throughout the lifecycle, from neurodevelopmental abnormalities in-utero to dementia in the elderly.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Prática Clínica Baseada em Evidências , Modelos Biológicos , Toxicologia/métodos , Xenobióticos/toxicidade , Animais , Poluentes Ambientais/toxicidade , Humanos , Toxicologia/tendências
5.
Dermatoendocrinol ; 8(1): e1248324, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27942348

RESUMO

Mounting evidence from observational and clinical trials indicates that optimal vitamin D reduces the risk of many diseases. We used observational studies and recent data on 25-hydroxyvitamin D [25(OH)D] concentrations of Canadians from Cycle 3 of the Canadian Health Measures Survey to estimate the reduction in disease incidence, mortality rates, and the total economic burden (direct plus indirect) of disease if 25(OH)D concentrations of all Canadians were raised to or above 100 nmol/L. Recently, the mean 25(OH)D concentration of Canadians varied depending on age and season (51-69 nmol/L), with an overall mean of 61 nmol/L. The diseases affected by 25(OH)D concentration included cancer, cardiovascular disease, dementia, diabetes mellitus, multiple sclerosis, respiratory infections, and musculoskeletal disorders. We used 25(OH)D concentration-health outcome relations for breast cancer and cardiovascular disease and results of clinical trials with vitamin D for respiratory infections and musculoskeletal disorders to estimate the reductions in disease burden for increased 25(OH)D concentrations. If all Canadians attained 25(OH)D concentrations>100 nmol/L, the calculated reduction in annual economic burden of disease was $12.5 ± 6 billion on the basis of economic burdens for 2016 and a reduction in annual premature deaths by 23,000 (11,000-34,000) on the basis of rates for 2011. However, the effects on disease incidence, economic burden, and mortality rate would be phased in gradually over several years primarily because once a chronic disease is established, vitamin D affects its progression only modestly. Nevertheless, national policy changes are justified to improve vitamin D status of Canadians through promotion of safe sun exposure messages, vitamin D supplement use, and/or facilitation of food fortification.

6.
Biomed Res Int ; 2016: 1624643, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27800487

RESUMO

Background. Many individuals have been exposed to organochlorinated pesticides (OCPs) through food, water, air, dermal exposure, and/or vertical transmission. Due to enterohepatic reabsorption and affinity to adipose tissue, OCPs are not efficiently eliminated from the human body and may accrue in tissues. Many epidemiological studies demonstrate significant exposure-disease relationships suggesting OCPs can alter metabolic function and potentially lead to illness. There is limited study of interventions to facilitate OCP elimination from the human body. This study explored the efficacy of induced perspiration as a means to eliminate OCPs. Methods. Blood, urine, and sweat (BUS) were collected from 20 individuals. Analysis of 23 OCPs was performed using dual-column gas chromatography with electron-capture detectors. Results. Various OCPs and metabolites, including DDT, DDE, methoxychlor, endrin, and endosulfan sulfate, were excreted into perspiration. Generally, sweat samples showed more frequent OCP detection than serum or urine analysis. Many OCPs were not readily detected in blood testing while still being excreted and identified in sweat. No direct correlation was found among OCP concentrations in the blood, urine, or sweat compartments. Conclusions. Sweat analysis may be useful in detecting some accrued OCPs not found in regular serum testing. Induced perspiration may be a viable clinical tool for eliminating some OCPs.


Assuntos
Hidrocarbonetos Clorados/farmacocinética , Praguicidas/farmacocinética , Suor/química , Adulto , Idoso , Cromatografia Gasosa , DDT/farmacocinética , Diclorodifenil Dicloroetileno/farmacocinética , Endossulfano/análogos & derivados , Endossulfano/farmacocinética , Endrin/farmacocinética , Poluentes Ambientais/farmacocinética , Feminino , Humanos , Masculino , Metoxicloro/farmacocinética , Pessoa de Meia-Idade , Adulto Jovem
7.
Biomed Res Int ; 2016: 6150976, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27314031

RESUMO

Emerging research suggests that much pediatric affliction has origins in the vulnerable phase of fetal development. Prenatal factors including deficiency of various nutrients and exposure to assorted toxicants are major etiological determinants of myriad obstetrical complications, pediatric chronic diseases, and perhaps some genetic mutations. With recent recognition that modifiable environmental determinants, rather than genetic predestination, are the etiological source of most chronic illness, modification of environmental factors prior to conception offers the possibility of precluding various mental and physical health conditions. Environmental and lifestyle modification through informed patient choice is possible but evidence confirms that, with little to no training in clinical nutrition, toxicology, or environmental exposures, most clinicians are ill-equipped to counsel patients about this important area. With the totality of available scientific evidence that now exists on the potential to modify disease-causing gestational determinants, failure to take necessary precautionary action may render members of the medical community collectively and individually culpable for preventable illness in children. We advocate for environmental health education of maternity health professionals and the widespread adoption and implementation of preconception care. This will necessitate the translation of emerging knowledge from recent research literature, to health professionals, to reproductive-aged women, and to society at large.


Assuntos
Ginecologia/normas , Saúde Materna/normas , Obstetrícia/normas , Guias de Prática Clínica como Assunto , Cuidado Pré-Concepcional/normas , Complicações na Gravidez/prevenção & controle , Canadá , Feminino , Humanos , Serviços de Saúde Materna/normas , Educação de Pacientes como Assunto/normas , Gravidez
9.
ScientificWorldJournal ; 2015: 318595, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26347061

RESUMO

In clinical medicine, increasing attention is being directed towards the important areas of nutritional biochemistry and toxicant bioaccumulation as they relate to human health and chronic disease. Optimal nutritional status, including healthy levels of vitamin D and essential minerals, is requisite for proper physiological function; conversely, accrual of toxic elements has the potential to impair normal physiology. It is evident that vitamin D intake can facilitate the absorption and assimilation of essential inorganic elements (such as calcium, magnesium, copper, zinc, iron, and selenium) but also the uptake of toxic elements (such as lead, arsenic, aluminum, cobalt, and strontium). Furthermore, sufficiency of essential minerals appears to resist the uptake of toxic metals. This paper explores the literature to determine a suitable clinical approach with regard to vitamin D and essential mineral intake to achieve optimal biological function and to avoid harm in order to prevent and overcome illness. It appears preferable to secure essential mineral status in conjunction with adequate vitamin D, as intake of vitamin D in the absence of mineral sufficiency may result in facilitation of toxic element absorption with potential adverse clinical outcomes.


Assuntos
Substâncias Perigosas/metabolismo , Minerais/metabolismo , Fenômenos Fisiológicos da Nutrição , Vitamina D/metabolismo , Suplementos Nutricionais , Substâncias Perigosas/toxicidade , Humanos , Minerais/efeitos adversos , Distúrbios Nutricionais/etiologia , Distúrbios Nutricionais/metabolismo , Vitamina D/efeitos adversos
10.
Behav Neurol ; 2015: 620143, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25722540

RESUMO

Juxtaposed alongside the ongoing rise in the incidence and prevalence of dementia, is the surge of recent research confirming widespread exposure and bioaccumulation of chemical toxicants. Evidence from sources such as the Centers for Disease Control reveals that most people have accrued varying degrees of assorted toxic pollutants including heavy metals, flame retardants, and pesticide residues within their bodies. It has been well established that many of these toxicants have neurodegenerative as well as neurodevelopmental impact as a result of various pathophysiologic mechanisms including neuronal mitochondrial toxicity and disruption of neurotransmitter regulation. Elimination of stockpiled toxicants from the body may diminish adverse toxicant impact on human biology and allow restoration of normal physiological function. Incorporating a review of medical literature on toxicant exposure and dementia with a case history of a lead-exposed individual diagnosed with dementia, this paper will discuss a much overlooked and potentially widespread cause of declining brain function and dementia.


Assuntos
Transtornos Cognitivos/induzido quimicamente , Demência/induzido quimicamente , Exposição Ambiental/efeitos adversos , Transtornos Mentais/induzido quimicamente , Idoso , Transtornos Cognitivos/diagnóstico , Demência/diagnóstico , Humanos , Masculino , Intoxicação por Mercúrio/fisiopatologia
11.
Obstet Gynecol Int ; 2015: 501829, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770200

RESUMO

Juxtaposed with monumental improvement in maternal-fetal outcomes over the last century, there has been the recent emergence of rising rates of gestational complications including preterm birth, operative delivery, and gestational diabetes. At the same time, there has been a burgeoning problem with widespread vitamin D deficiency among populations of many developed nations. This paper provides a brief review of potential health outcomes recently linked to gestational vitamin D deficiency, including preterm birth, cesarean delivery, and gestational diabetes. Although immediate costs for obstetric complications related to gestational vitamin D insufficiency may be modest, the short- and long-term costs for pediatric healthcare resulting from such gestational complications may be enormous and present an enduring burden on healthcare systems. With increasing evidence pointing to fetal origins of some later life disease, securing vitamin D sufficiency in pregnancy appears to be a simple, safe, and cost-effective measure that can be incorporated into routine preconception and prenatal care in the offices of primary care clinicians. Education on gestational nutritional requirements should be a fundamental part of medical education and residency training, instruction that has been sorely lacking to date.

12.
PLoS One ; 9(12): e114295, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25504057

RESUMO

BACKGROUND: Perfluoroalkyl acids (PFAAs) are a family of commonly used synthetic chemicals that have become widespread environmental contaminants. In human serum, perfluorohexane sulfonate (PFHxS), perflurooctane sulfonate (PFOS), and perfluorooctanoate (PFOA) are most frequently detected, in part owing to their long elimination half-lives of between 3.8 yrs (PFOA) and 8.5 yrs (PFHxS). These PFAAs also cross the placenta and have been associated with developmental toxicity, and some are considered likely human carcinogens. Interventions to eliminate PFAAs in highly contaminated individuals would reduce future health risks, but minimal research has been conducted on methods to facilitate accelerated human clearance of these persistent substances. METHODS: Six patients with elevated serum concentrations from a single family were treated by intermittent phlebotomy over a 4-5 year period at intervals similar to, or less frequent than what is done for routine blood donation at Canadian Blood Services. The apparent elimination half-life (HLapp) for PFHxS, PFOS, and PFOA in this treated population was calculated in each patient and compared to the intrinsic elimination half-lives (HLin) from a literature reference population of untreated fluorochemical manufacturing plant retirees (n = 26, age >55 yrs). RESULTS: For all three PFAAs monitored during phlebotomy, HLapp in each of the family members (except the mother, who had a low rate of venesection) was significantly shorter than the geometric mean HL measured in the reference population, and in some cases were even shorter compared to the fastest eliminator in the reference population. CONCLUSION: This study suggests significantly accelerated PFAA clearance with regular phlebotomy treatment, but the small sample size and the lack of controls in this clinical intervention precludes drawing firm conclusions. Given the minimal risks of intermittent phlebotomy, this may be an effective and safe clinical intervention to diminish the body burden of PFAAs in highly exposed people.


Assuntos
Exposição Ambiental/efeitos adversos , Poluentes Ambientais/farmacocinética , Fluorocarbonos/farmacocinética , Flebotomia , Adolescente , Feminino , Meia-Vida , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
13.
Can Fam Physician ; 60(9): 797-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25217672
14.
Can Fam Physician ; 60(8): 709-10, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25122812
16.
Can Fam Physician ; 60(6): 533-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24925942

RESUMO

OBJECTIVE: To explore the underlying causation of unexplained multimorbidity with sensitivities and to discuss the management of patients who present with this perplexing condition. SOURCES OF INFORMATION: Medical and scientific literature was used from MEDLINE (PubMed), several books, toxicology and allergy journals, conference proceedings, government publications, and environmental health periodicals. MAIN MESSAGE: Multimorbidity with sensitivities has become an increasingly common and confusing primary care dilemma. Escalating numbers of debilitated individuals are now presenting to family physicians and specialists with multisystem health complaints, including sensitivities and fatigue, with no obvious causation, a paucity of laboratory findings, and a lack of straightforward solutions. In the recent scientific literature, there is discussion of sensitivity-related illness, an immune-mediated disorder that frequently manifests with multisystem symptoms, commonly including sensitivities and fatigue. This condition appears to be originally caused by adverse environmental exposures and toxicant bioaccumulation-an increasingly prevalent and well-documented problem in contemporary culture. CONCLUSION: Various toxic exposures and their bioaccumulation within the body frequently manifest as sensitivity-related illness. In clinical settings, patients with this disorder often present with otherwise unexplained multimorbidity and sensitivities. The health status of patients with this condition can be ameliorated by removing triggers (eg, scented products), optimizing biochemistry, removing further sources of toxicant exposures, and eliminating the internal dose of persistent toxicants.


Assuntos
Exposição Ambiental/efeitos adversos , Doença Ambiental , Hipersensibilidade , Comorbidade , Gerenciamento Clínico , Doença Ambiental/diagnóstico , Doença Ambiental/epidemiologia , Doença Ambiental/etiologia , Doença Ambiental/terapia , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/fisiopatologia , Hipersensibilidade/terapia , Prevalência , Avaliação de Sintomas
17.
Gastroenterol Res Pract ; 2014: 293206, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24693281

RESUMO

There has been increasing recognition in the medical community and the general public of the widespread prevalence of gluten sensitivity. Celiac disease (CD) was initially believed to be the sole source of this phenomenon. Signs and symptoms indicative of nonceliac gluten sensitivity (NCGS), in which classical serum and intestinal findings of CD may be absent, have been frequently reported of late. Clinical manifestations in patients with NCGS are characteristically triggered by gluten and are ameliorated or resolved within days to weeks of commencing a gluten-free diet. Emerging scientific literature contains several reports linking gluten sensitivity states with neuropsychiatric manifestations including autism, schizophrenia, and ataxia. A clinical review of gluten sensitivity is presented alongside a case illustrating the life-changing difference achieved by gluten elimination in a patient with a longstanding history of auditory and visual hallucinations. Physicians in clinical practice should routinely consider sensitivity issues as an etiological determinant of otherwise inexplicable symptoms. Pathophysiologic mechanisms to explain the multisystem symptomatology with gluten sensitivity are considered.

18.
J Toxicol ; 2013: 370460, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260033

RESUMO

Background. Increasing concern is evident about contamination of foodstuffs and natural health products. Methods. Common off-the-shelf varieties of black, green, white, and oolong teas sold in tea bags were used for analysis in this study. Toxic element testing was performed on 30 different teas by analyzing (i) tea leaves, (ii) tea steeped for 3-4 minutes, and (iii) tea steeped for 15-17 minutes. Results were compared to existing preferred endpoints. Results. All brewed teas contained lead with 73% of teas brewed for 3 minutes and 83% brewed for 15 minutes having lead levels considered unsafe for consumption during pregnancy and lactation. Aluminum levels were above recommended guidelines in 20% of brewed teas. No mercury was found at detectable levels in any brewed tea samples. Teas contained several beneficial elements such as magnesium, calcium, potassium, and phosphorus. Of trace minerals, only manganese levels were found to be excessive in some black teas. Conclusions. Toxic contamination by heavy metals was found in most of the teas sampled. Some tea samples are considered unsafe. There are no existing guidelines for routine testing or reporting of toxicant levels in "naturally" occurring products. Public health warnings or industry regulation might be indicated to protect consumer safety.

19.
ISRN Toxicol ; 2013: 483832, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24083032

RESUMO

Perfluorinated compounds (PFCs) are man-made organofluorine chemicals manufactured and marketed for their stain-resistant properties. Polychlorinated biphenyls (PCBs) are anthropogenic organochlorine compounds previously used in various industrial and chemical applications prior to being banned in the Western world in the 1970s. Both PFCs and PCBs are persistent contaminants within the human organism and both have been linked to adverse health sequelae. Data is lacking on effective means to facilitate clearance of PFCs and PCBs from the body. Methods. Blood, urine, and sweat were collected from 20 individuals (10 healthy participants and 10 participants with assorted health problems) and analyzed for PFCs and PCBs using high performance liquid chromatography tandem mass spectrometry. Results. Some individual PCB congeners, but not all, were released into sweat at varying concentrations. None of the PFCs found in serum testing appeared to be excreted efficiently into perspiration. Conclusions. Induced perspiration may have some role in facilitating elimination of selected PCBs. Sweat analysis may be helpful in establishing the existence of some accrued PCBs in the human body. Sweating does not appear to facilitate clearance of accrued PFHxS (perfluorohexane sulfonate), PFOS (perfluorooctane sulfonate), or PFOA (perfluorooctanoic acid), the most common PFCs found in the human body.

20.
ISRN Toxicol ; 2013: 657849, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24106616

RESUMO

Background. While perfluorinated compounds (PFCs) are a family of commonly used synthetic compounds with many applications, some PFCs remain persistent within the human body due, in part, to enterohepatic recirculation and renal tubular reabsorption. With increasing recognition of potential harm to human health associated with PFC bioaccumulation, interventions to facilitate elimination of these toxicants are welcome in order to potentially preclude or overcome illness. Minimal research has been undertaken thus far on methods to accelerate human clearance of PFCs. Methods. To test for possible oral treatments to hasten PFC elimination, a group of individuals with elevated PFC levels was treated with cholestyramine (CSM) and, after a break, was subsequently treated with Chlorella pyrenoidosa (CP). Stool samples were collected from all participants (i) prior to any treatment, (ii) during treatment with CSM, and (iii) during treatment with CP. Results. With CSM treatment, significant levels of three distinct PFCs were found in all stools, while levels were mostly undetectable prior to treatment. Following treatment with oral CP, undetectable or very low levels of all PFCs were noted in each sample tested. Conclusion. CSM appears to facilitate elimination of some common PFCs and may have some role in the clinical management of patients with accrued PFCs.

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