Effects of prolonged application of peracetic acid-based disinfectant on recirculating aquaculture systems stocked with Atlantic salmon parr.

The use of recirculating aquaculture systems (RAS) for Atlantic salmon (Salmo salar) production has become increasingly common. RAS water disinfection plays a crucial role on its biosecurity. Peracetic acid (PAA) is a promising disinfectant due to its powerful oxidative properties, broad antimicrobial spectrum, and rapid degradation into no harmful compounds. This study focused on assessing the consequences of prolonged application of a PAA-based disinfectant in a RAS stocked with salmon parr. The experiment included three treatment groups in triplicate: 0 mg/L PAA (control), 0.1 mg/L PAA, and 1 mg/L PAA, using nine-replicated RAS with a total of 360 fish (14.8 ±â€¯2.3 g; N = 40/RAS). The study spanned 28 days, with samples collected on days 0, 14, and 28. The analyzed parameters were water quality, and fish parameters, including external welfare indicators, gill histology, total antioxidant capacity (TAC), reactive oxygen species/reactive nitrogen species (ROC/RNC), oxidative stress biomarkers related to DNA and protein, cellular DNA damage, and global gene expression. While water quality remained relatively stable, there was an increase in bacterial populations in the groups exposed to PAA, particularly 1 mg/L PAA. Fish weight did not differ between the control and PAA-exposed groups. TAC, ROC/RNC, and oxidative stress biomarkers exhibited similar trends. The study identified >400 differentially expressed genes (DEGs) in the skin, gill, and olfactory organ, with many of these DEGs associated with immune responses. Comparing the transcriptomic profiles of the three tissue organs revealed that the olfactory organ was the most reactive to PAA treatment. This study shows that calculated PAA concentrations of 0.1 mg/L and 1 mg/L in the pump-sump, contributed to an increase of bacteria whereas no detectable differences in health and welfare of salmon parr were found. These findings are promising for the implementation of PAA-based disinfectants in RAS stoked with Atlantic salmon parr.

A genome-wide association study provides insights into the genetic etiology of 57 essential and non-essential trace elements in humans.

Trace elements are important for human health but may exert toxic or adverse effects. Mechanisms of uptake, distribution, metabolism, and excretion are partly under genetic control but have not yet been extensively mapped. Here we report a comprehensive multi-element genome-wide association study of 57 essential and non-essential trace elements. We perform genome-wide association meta-analyses of 14 trace elements in up to 6564 Scandinavian whole blood samples, and genome-wide association studies of 43 trace elements in up to 2819 samples measured only in the Trøndelag Health Study (HUNT). We identify 11 novel genetic loci associated with blood concentrations of arsenic, cadmium, manganese, selenium, and zinc in genome-wide association meta-analyses. In HUNT, several genome-wide significant loci are also indicated for other trace elements. Using two-sample Mendelian randomization, we find several indications of weak to moderate effects on health outcomes, the most precise being a weak harmful effect of increased zinc on prostate cancer. However, independent validation is needed. Our current understanding of trace element-associated genetic variants may help establish consequences of trace elements on human health.

Skogholt's disease-A tauopathy precipitated by iron and copper?

BACKGROUND: It has been suggested that Skogholt's disease is a new neurological disease entity. The disease, confined to a family line in Hedmark county, Norway, usually affects both the brain and peripheral nerves. Typical findings are white matter lesions in the brain, myelin damage in peripheral nerves, and discolored cerebrospinal fluid with high concentrations of protein, copper, and iron. Little is known about the natural progression of the disease and its underlying cause, but the high level of copper and iron in the cerebrospinal fluid may cause or exacerbate inflammation in the central nervous system. METHODS: The present clinical study further explores the disease progression with clinical chemistry analyses and mass spectrometry of blood and cerebrospinal fluid (CSF) from patients and controls. Findings are corroborated with cognitive assessments. RESULTS: Pathological changes in CSF with low amyloid-ß42 and high levels of tau proteins, total protein, copper, and iron, were discovered among Skogholt patients. The Montreal Cognitive Assessment identified 36 % of the patients as below normal range, while most patients performed slower than the norm mean time on the Trail Making Test. Mini-Mental Status Examination disclosed only minor deviations. CONCLUSION: The findings in the present study strengthen our initial suggestion that Skogholt's disease most likely is a new neurological disorder and provide new clues to its cause: The disease may belong to the family of neurodegenerative disorders termed tauopathies. The increased level of copper and iron may contribute to neuroinflammation as these metals also have been associated with other neurodegenerative disorders. Although the causes of neurodegenerative disorders are currently largely unknown, studies on rare disease entities, such as the present one, may increase the understanding of neurodegeneration in general.

Trace elements in whole blood in the general population in Trøndelag County, Norway: The HUNT3 Survey.

BACKGROUND: Biomonitoring of a cohort within a large health survey can provide reliable information on trace element status. The main aims of this study were 1) to determine the concentrations of 28 trace elements in whole blood samples from the general population of the Nord-Trøndelag region, Norway, and 2) to investigate how trace element concentrations vary with geographical area, lifestyle, and socio-demographic factors. METHODS: Whole blood samples were collected in the third survey of the Trøndelag Health Survey (HUNT3), a large population-based study in Norway. In total, 1011 whole blood samples from individuals aged 20-91 years were analyzed using high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS). We compared trace element concentrations (As, B, Be, Br, Ca, Cd, Cr, Cs, Cu, Ga, Au, In, Fe, Pb, Hg, Tl, Mg, Mn, Mo, Ni, Rb, Sc, Se, Ag, Sr, Sn, W and Zn) between three geographical areas (coastal, fjord/town, inland/mountain) using multivariable linear regression and assessed differences in trace element concentrations with socio-demographic and lifestyle factors using general linear models. RESULTS: Trace element concentrations were generally comparable to levels reported in other recent studies and suggest low exposure to toxic trace elements in the region. We found geographical differences in concentrations of 19 trace elements. As, Br, Hg, and Se concentrations were higher on the coast compared to the fjord/town and inland/mountain areas, suggesting that the marine environment is an important source of exposure for these trace elements. In addition, socio-demographic and lifestyle characteristics, particularly age and sex, were associated with differences in trace element concentrations. CONCLUSIONS: We report concentrations of 28 trace elements in the general population of a rural region with low exposure to pollution. Whole blood concentrations of trace elements varied with geographical area, the participants' lifestyle, and socio-demographic characteristics, highlighting the importance of considering these factors when evaluating trace element status in a population.

Trace Elements in the Large Population-Based HUNT3 Survey.

The Nord-Trøndelag Health Study (The HUNT Study) is a large health survey population study in the county of Trøndelag, Norway. The survey has been repeated four times in about 10-year intervals. In the HUNT3 survey (2006-2008), we collected 28,000 samples for trace element analysis. Blood samples from 758 healthy persons without known occupational exposure were selected for multielement analysis of a small sample of blood (0.25 mL). The aim of the study was to determine the minimum blood volume that can be used for the analytical procedure and to compare our results with previously published results of similar surveys in healthy populations. Samples were digested and the concentration of selected trace elements was determined by ICP-MS. We report results on essential elements (B, Co, Cu, Mn, Se and Zn) as well as non-essential elements (As, Be, Br, Cd, Cs, In, La, Pb, Hg, Nd, Ni, Nb, Pd, Pt, Sm, Ta and Sn). Results are similar to previous studies on the HUNT3 population, and with a few exceptions, our data compares very well with results obtained in recent studies from other countries. We wanted to test a minimum volume of blood in a large-scale analytical program. For a number of nonessential elements, our results were below the limit of detection. We suggest that future studies using similar ICP-MS equipment as analytical tool should use at least 0.5 mL of blood.

Essential trace elements in Norwegian obese patients before and 12 months after Roux-en-Y gastric bypass surgery: Copper, manganese, selenium and zinc.

OBJECTIVES: The objective of the present study was to assess trace element status in morbidly obese subjects before and one year after Roux-en-Y gastric bypass (RYGB) in order to identify possible deficiencies. METHODS: The study population included 46 patients in the age range 27-59 years, the majority (85 %) were women. The enrolled patients attended an eight week course on lifestyle changes before bariatric surgery. After RYGB they were recommended daily micronutrient supplements with a commonly used multivitamin-mineral tablet in addition to intramuscular vitamin B12 injections (1 mg) every third month for 12 months. Whole blood concentrations of Cu, Mn, Se and Zn were determined using high resolution inductively coupled plasma mass spectrometry. RESULTS: During the 12 months follow up after bariatric surgery, the patients had lost mean 32.3 kg and median whole blood concentrations of Cu (-16 %) were reduced, Mn (+14 %) and Zn (+6%) were increased, while the Se values were essentially unchanged. Compared with reference ranges, median postoperative concentrations of all essential trace elements were either below (Zn) or in the lower reference range (Cu, Mn, Se). CONCLUSION: Essential trace elements were below or in the lower reference range twelve months after RYGB. Our results indicate a need for updated guidelines in Nordic countries for trace metal monitoring and supplements in patients after bariatric surgery, especially when gastric bypass surgery is used. Further studies are required to explore and prevent trace element deficiency related to obesity and bariatric surgery.

Cadmium, lead and mercury in Norwegian obese patients before and 12 months after bariatric surgery.

PURPOSE: Previous studies have suggested a role for the toxic elements lead (Pb), mercury (Hg) and cadmium (Cd) in the development of insulin resistance and hypertension. Increased blood Pb levels have been reported after bariatric surgery and weight loss. As about 80% of patients undergoing bariatric surgery are women, most of them of childbearing age, there are concerns regarding fetal exposure to toxic trace elements. We measured whole blood Hg, Pb and Cd concentrations in morbidly obese patients before and 12 months after Roux-en-Y gastric bypass (RYGB). PATIENTS AND METHODS: Forty-six patients eligible for bariatric surgery were recruited at Innlandet Hospital Trust, Norway (2012-2014). The majority were women and 54% were of reproductive age. Whole blood samples were collected prior to and 12 months after surgery. Trace element concentrations were measured using mass spectrometry (HR-ICP-MS). RESULTS: Median whole blood Pb concentrations increased by 73% during the 12 months study period while Hg and Cd decreased by 31% and 27%, respectively. We found a negative correlation between Pb levels before surgery and BMI (p = 0.02). Before surgery patients with hypertension had significantly higher median whole blood Hg levels compared to patients with normal blood pressure (p < 0.001). CONCLUSION: One year after bariatric surgery, the median whole blood Pb concentration was increased, while Hg and Cd concentrations were decreased. The majority of bariatric surgery patients are women of reproductive age and weight loss is associated with improved fertility. As even low dose Pb exposure during fetal life is associated with negative effects on the central nervous system, the observed increase in whole blood Pb after weight loss causes concern. Further studies are needed to elucidate these observations.

Trace element status in patients with type 2 diabetes in Norway: The HUNT3 Survey.

Several epidemiological studies have indicated that a number of trace elements may play a role in type 2 diabetes (T2D). We investigated the association between prevalent T2D and the concentrations of 25 trace elements in whole blood, and the relationships between T2D duration and blood levels of the trace elements that we found to be related to T2D prevalence. In this population based case-control study, 267 patients with self-reported T2D and 609 controls (frequency matched), were selected from the third Nord-Trøndelag Health Survey. Trace element blood levels were determined by high resolution inductively coupled plasma-mass spectrometry. Multivariable conditional logistic regression and multivariable linear regression were used to estimate associations. The prevalence of T2D was positively associated with boron, calcium and silver, and inversely associated with indium, lead and magnesium (Ptrend<0.05). We found no statistical evidence for associations between blood levels of arsenic, bromine, cadmium, cesium, chromium, copper, gallium, gold, manganese, mercury, molybdenum, nickel, rubidium, selenium, strontium, tantalum, thallium, tin and zinc and T2D prevalence. After corrections for multiple testing, associations remained significant for calcium and lead (Qtrend<0.05), and borderline significant for magnesium, silver and boron. With increasing disease duration, higher calcium levels were observed (P<0.05). This study suggests an association between prevalent T2D and blood levels of boron, calcium, indium, lead, magnesium and silver.

Trace elements in early phase type 2 diabetes mellitus-A population-based study. The HUNT study in Norway.

Differences in trace elements levels between individuals with type 2 diabetes and controls have been reported in several studies in various body fluids and tissues, but results have been inconsistent. In order to examine trace element levels in the early phase of type 2 diabetes, we investigated the association between whole blood levels of 26 trace elements and the prevalence of previously undiagnosed, screening-detected type 2 diabetes. The study was conducted as a case-control study nested within the third survey of the population-based Nord-Trøndelag Health Study (HUNT3 Survey). Among participants without previously known diabetes, 128 cases of type 2 diabetes were diagnosed in people with a high diabetes risk score (FINDRISC≥15), and frequency-matched for age and sex with 755 controls. Blood samples were analyzed by high resolution inductively coupled plasma mass spectrometry. Associations between trace element levels and the prevalence of previously undiagnosed type 2 diabetes were evaluated with multivariable conditional logistic regression controlling for age, sex, body mass index, waist-to-hip ratio, education, income, smoking and family history of diabetes. The prevalence of previously undiagnosed type 2 diabetes increased across tertiles/quartiles for cadmium, chromium, iron, nickel, silver and zinc, and decreased with increasing quartiles of bromine (Ptrend<0.05). After corrections for multiple testing, associations for chromium remained significant (Qtrend<0.05), while associations for iron and silver were borderline significant. No associations were found for arsenic, boron, calcium, cesium, copper, gallium, gold, indium, lead, magnesium, manganese, mercury, molybdenum, rubidium, selenium, strontium, tantalum, thallium and tin. Our results suggest a possible role of bromine, cadmium, chromium, iron, nickel, silver and zinc in the development of type 2 diabetes.

Evaluation of Macro- and Microelement Levels in Black Tea in View of Its Geographical Origin.

The aim of this study was to evaluate the elemental composition of black tea samples and their infusions in view of their geographical origin. In total, 14 elements were analyzed, 13 (Ca, K, Mg, Na, Mn, Fe, Zn, Cu, Cr, Ni, Co, Cd, and Pb) by flame atomic absorption spectrometry, and P by UV-Vis spectrometry, after mineralization of samples. It was found that K was the most abundant macroelement in the analyzed samples, whereas among microelements, the highest concentration was found for Mn. Based on the obtained data, the percentage of elements leached into the infusions as well as the daily elemental intake from tea were calculated. The daily intake from tea was compared to the recommended daily allowances (RDAs), and the highest percentages of the RDAs were found for Mn (15 %) and Co (10 %). To study the relations between elemental composition and country of origin of samples, factor analysis and cluster analysis were applied. These multivariate techniques proved to be efficient tools able to differentiate samples according to their provenance as well as plantation within the common regions.

Multi-element analysis of airborne particulate matter from different work tasks during subsea tunnel rehabilitation work.

Tunnel rehabilitation work involves exposure to various air contaminants, including airborne particulate matter (APM). Little is known on the contents of different chemical components of APM generated during tunnel work. The objective of the present study was to characterize exposure to APM and various elements for different job categories in different size fractions of APM during a subsea tunnel rehabilitation project carried out in Western Norway. Personal as well as stationary samples of inhalable, thoracic and respirable dust were collected from workers divided into 11 different job categories based on work operations performed, and air concentrations of a range of elements were determined using high-resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS). Overall, APM concentrations were low, but with some measurements exceeding the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) for inhalable particles, and considerable proportions of respirable and especially inhalable APM exceeding 10% of the TLVs. For most elements, air concentrations measured were quite low, in the ng/m(3) range, except for the major crustal elements Si, Fe, Al, and Mg, which were found to be in the µg/m(3) range. Asphalt millers overall had the highest exposure levels for APM and most measured elements; for instance, mean concentrations of V, Rb, and Mn were 380, 210, and 2000 ng/m(3) in inhalable and 33, 44, and 310 ng/m(3) in respirable APM. Mounting PVC membrane seemed to generate elevated levels of Cr, Zn, Sn, Pb, Sb, As, Mn, Fe, and Ni, whereas typical bedrock elements were elevated during drilling activities compared to the low exposed categories lead car drivers, foremen/surveyors, drivers of heavy-duty vehicles, and electricians. Overall, stationary samples contained lower amounts of dust and elemental constituents compared to personal samples. Elemental air concentrations were highly variable with occasional elevated values for APM and certain elements, particularly Cr and Zn.

Population data on calcium in drinking water and hip fracture: An association may depend on other minerals in water. A NOREPOS study.

BACKGROUND: The Norwegian population has among the highest hip fracture rates in the world. The incidence varies geographically, also within Norway. Calcium in drinking water has been found to be beneficially associated with bone health in some studies, but not in all. In most previous studies, other minerals in water have not been taken into account. Trace minerals, for which drinking water can be an important source and even fulfill the daily nutritional requirement, could act as effect-modifiers in the association between calcium and hip fracture risk. The aim of the present study was to investigate the association between calcium in drinking water and hip fracture, and whether other water minerals modified this association. MATERIALS AND METHODS: A survey of trace metals in 429 waterworks, supplying 64% of the population in Norway, was linked geographically to the home addresses of patients with incident hip fractures (1994-2000). Drinking water mineral concentrations were divided into "low" (below and equal waterworks average) and "high" (above waterworks average). Poisson regression models were fitted, and all incidence rate ratios (IRRs) were adjusted for age, geographic region, urbanization degree, type of water source, and pH of the water. Effect modifications were examined by stratification, and interactions between calcium and magnesium, copper, zinc, iron and manganese were tested both on the multiplicative and the additive scale. Analyses were stratified on gender. RESULTS: Among those supplied from the 429 waterworks (2,110,916 person-years in men and 2,397,217 person-years in women), 5433 men and 13,493 women aged 50-85 years suffered a hip fracture during 1994-2000. Compared to low calcium in drinking water, a high level was associated with a 15% lower hip fracture risk in men (IRR=0.85, 95% CI: 0.78, 0.91) but no significant difference was found in women (IRR=0.98, 95%CI: 0.93-1.02). There was interaction between calcium and copper on hip fracture risk in men (p=0.051); the association between calcium and hip fracture risk was stronger when the copper concentration in water was high (IRR=0.52, 95% CI: 0.35, 0.78) as opposed to when it was low (IRR=0.88, 95% CI: 0.81, 0.94). This pattern persisted also after including potential confounding factors and other minerals in the model. No similar variation in risk was found in women. CONCLUSION: In this large, prospective population study covering two thirds of the Norwegian population and comprising 19,000 hip fractures, we found an inverse association between calcium in drinking water and hip fracture risk in men. The association was stronger when the copper concentration in the water was high.

Iron and copper in progressive demyelination--New lessons from Skogholt's disease.

The pathophysiological mechanisms of progressive demyelinating disorders including multiple sclerosis are incompletely understood. Increasing evidence indicates a role for trace metals in the progression of several neurodegenerative disorders. The study of Skogholt disease, a recently discovered demyelinating disease affecting both the central and peripheral nervous system, might shed some light on the mechanisms underlying demyelination. Cerebrospinal fluid iron and copper concentrations are about four times higher in Skogholt patients than in controls. The transit into cerebrospinal fluid of these elements from blood probably occurs in protein bound form. We hypothesize that exchangeable fractions of iron and copper are further transferred from cerebrospinal fluid into myelin, thereby contributing to the pathogenesis of demyelination. Free or weakly bound iron and copper ions may exert their toxic action on myelin by catalyzing production of oxygen radicals. Similarities to demyelinating processes in multiple sclerosis and other myelinopathies are discussed.

Essential and non-essential elements in natural vegetation in southern Norway: contribution from different sources.

Concentrations of essential and non-essential elements in five widespread species of natural boreal vegetation were studied with respect to seasonal variation and contribution from different sources. The plant species included in the study were Betula pubescens, Sorbus aucuparia, Vaccinium myrtillus, Vaccinium uliginosum, Calluna vulgaris and Deschampsia flexuosa. Concentrations of elements essential to plants remained essentially constant or decreased slightly throughout the growing season. Concentrations of most non-essential elements increased or tended to increase on a dry mass basis from June to July as well as from July to September. The increasing trend for these elements was observed for all species except C. vulgaris. Principal component analysis (PCA) of the material indicated a common source for many of the non-essential elements; Sc, Ti, V, Ga, As, Y, Sb, lanthanides, Pb, Bi, and U, i.e. both elements presumably of geogenic origin and elements associated with trans-boundary air pollution. Uptake by plant roots appeared to be the main source of nutrient elements as well as some non-essential elements.

The neurotoxicity of iron, copper and manganese in Parkinson's and Wilson's diseases.

Impaired cellular homeostasis of metals, particularly of Cu, Fe and Mn may trigger neurodegeneration through various mechanisms, notably induction of oxidative stress, promotion of α-synuclein aggregation and fibril formation, activation of microglial cells leading to inflammation and impaired production of metalloproteins. In this article we review available studies concerning Fe, Cu and Mn in Parkinson's disease and Wilson's disease. In Parkinson's disease local dysregulation of iron metabolism in the substantia nigra (SN) seems to be related to neurodegeneration with an increase in SN iron concentration, accompanied by decreased SN Cu and ceruloplasmin concentrations and increased free Cu concentrations and decreased ferroxidase activity in the cerebrospinal fluid. Available data in Wilson's disease suggest that substantial increases in CNS Cu concentrations persist for a long time during chelating treatment and that local accumulation of Fe in certain brain nuclei may occur during the course of the disease. Consequences for chelating treatment strategies are discussed.

Do cadmium, lead, and aluminum in drinking water increase the risk of hip fractures? A NOREPOS study.

The aim of this study was to investigate relations between cadmium, lead, and aluminum in municipality drinking water and the incidence of hip fractures in the Norwegian population. A trace metals survey in 566 waterworks was linked geographically to hip fractures from hospitals throughout the country (1994-2000). In all those supplied from these waterworks, 5,438 men and 13,629 women aged 50-85 years suffered a hip fracture. Poisson regression models were fitted, adjusting for age, region of residence, urbanization, and type of water source as well as other possibly bone-related water quality factors. Effect modification by background variables and interactions between water quality factors were examined (correcting for false discovery rate). Men exposed to a relatively high concentration of cadmium (IRR = 1.10; 95 % CI 1.01, 1.20) had an increased risk of fracture. The association between relatively high lead and hip fracture risk was significant in the oldest age group (66-85 years) for both men (IRR = 1.11; 95 % CI 1.02, 1.21) and women (IRR = 1.10; 95 % CI 1.04, 1.16). Effect modification by degree of urbanization on hip fracture risk in men was also found for all three metals: cadmium, lead, and aluminum. In summary, a relatively high concentration of cadmium, lead, and aluminum measured in drinking water increased the risk of hip fractures, but the associations depended on gender, age, and urbanization degree. This study could help in elucidating the complex effects on bone health by risk factors found in the environment.

Nationwide data on municipal drinking water and hip fracture: could calcium and magnesium be protective? A NOREPOS study.

Norway has a high incidence of hip fractures, and the incidence varies by degree of urbanization. This variation may reflect a difference in underlying environmental factors, perhaps variations in the concentration of calcium and magnesium in municipal drinking water. A trace metal survey (1986-1991) in 556 waterworks (supplying 64% of the Norwegian population) was linked geographically to hip fractures from hospitals throughout the country (1994-2000). In all, 5472 men and 13,604 women aged 50-85years suffered a hip fracture. Poisson regression models were fitted, adjusting for age, urbanization degree, region of residence, type of water source, and pH. The concentrations of calcium and magnesium in drinking water were generally low. An inverse association was found between concentration of magnesium and risk of hip fracture in both genders (IRR men highest vs. lowest tertile=0.80, 95% CI: 0.74, 0.87; IRR women highest vs. lowest tertile=0.90, 95% CI: 0.85, 0.95), but no consistent association between calcium and hip fracture risk was observed. The highest tertile of urbanization degree (city), compared to the lowest (rural), was related to a 23 and 24% increase in hip fracture risk in men and women, respectively. The association between magnesium and hip fracture did not explain the variation in hip fracture risk between city and rural areas. Magnesium in drinking water may have a protective role against hip fractures; however this association should be further investigated.

Metal concentrations in cerebrospinal fluid and blood plasma from patients with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal degenerative disorder of motor neurons. The cause of this degeneration is unknown, and different causal hypotheses include genetic, viral, traumatic and environmental mechanisms. In this study, we have analyzed metal concentrations in cerebrospinal fluid (CSF) and blood plasma in a well-defined cohort (n = 17) of ALS patients diagnosed with quantitative electromyography. Metal analyses were performed with high-resolution inductively coupled plasma mass spectrometry. Statistically significant higher concentrations of manganese, aluminium, cadmium, cobalt, copper, zinc, lead, vanadium and uranium were found in ALS CSF compared to control CSF. We also report higher concentrations of these metals in ALS CSF than in ALS blood plasma, which indicate mechanisms of accumulation, e.g. inward directed transport. A pattern of multiple toxic metals is seen in ALS CSF. The results support the hypothesis that metals with neurotoxic effects are involved in the pathogenesis of ALS.

Manganese in cerebrospinal fluid and blood plasma of patients with amyotrophic lateral sclerosis.

Neurotoxic properties of manganese (Mn) are well documented. It is less known that Mn contributes to the development of neurodegenerative disorders in the general population. This study presents Mn data from patients with amyotrophic lateral sclerosis (ALS) in a well-defined cohort diagnosed by electrophysiological methods. Cerebrospinal fluid (CSF) and plasma were collected from patients and controls. Mn concentrations were analyzed by high-resolution inductively coupled plasma mass spectrometry. Concentrations of Mn were significantly higher in ALS CSF (median 5.67 µg/L) than in CSF from controls (median 2.08 µg/L). Also, ALS CSF Mn concentrations were higher than ALS plasma Mn concentrations (median 0.91 µg/L), suggesting transport of Mn into the central nervous system. The properties of barrier systems between blood and the brain are discussed and the possibility of Mn accumulation contributing to the relentless course of ALS is introduced.

Iron mobilization using chelation and phlebotomy.

Knowledge of the basic mechanisms involved in iron metabolism has increased greatly in recent years, improving our ability to deal with the huge global public health problems of iron deficiency and overload. Several million people worldwide suffer iron overload with serious clinical implications. Iron overload has many different causes, both genetic and environmental. The two most common iron overload disorders are hereditary haemochromatosis and transfusional siderosis, which occurs in thalassaemias and other refractory anaemias. The two most important treatment options for iron overload are phlebotomy and chelation. Phlebotomy is the initial treatment of choice in haemochromatosis, while chelation is a mainstay in the treatment of transfusional siderosis. The classical iron chelator is deferoxamine (Desferal), but due to poor gastrointestinal absorption it has to be administered intravenously or subcutaneously, mostly on a daily basis. Thus, there is an obvious need to find and develop new effective iron chelators for oral use. In later years, particularly two such oral iron chelators have shown promise and have been approved for clinical use, namely deferiprone (Ferriprox) and deferasirox (Exjade). Combined subcutaneous (deferoxamine) and oral (deferiprone) treatment seems to hold particular promise.