Particle and metal exposure in Parisian subway: Relationship between exposure biomarkers in air, exhaled breath condensate, and urine.

Subway particulate toxicity results from in vitro and in vivo studies diverge and call for applied human research on outcomes from chronic exposures and potential exposure biomarkers. We aimed to (1) quantify airborne particulate matter (PM) concentrations (mass and number) and metal concentrations in exhaled breath condensate (EBC), urine, and PM; (2) investigate their associations (EBC vs. PM vs. urine); and (3) assess the relevance of EBC in biomonitoring. Nine subway workers in three jobs: station agents, locomotive operators and security guards were monitored during their 6-h shifts over two consecutive weeks. Six-hour weighed average mass concentrations expressed as PM10, PM2.5 and their metal concentrations were determined. Urine and EBC samples were collected pre- and post-shift. Ultrafine particle (UFP) number concentrations were quantified in PM and EBC samples. Metal concentrations in urine and EBC were standardized by creatinine and EBC volume, respectively, and log-transformed. Associations were investigated using Pearson correlation and linear mixed regression models, with participant's ID as random effect. PM concentrations were below occupational exposure limits (OEL) and varied significantly between jobs. Locomotive operators had the highest exposure (189 and 137 µg/m3 for PM10 and PM2.5, respectively), while station agents had the highest UFP exposure (1.97 × 104 particles/cm3). Five metals (Al, Fe, Zn, Cu, and Mn) in PM2.5 and three (Al, Fe, and Zn) in PM10 were above the limit of quantification (LOQ). Fe, Cu, Al and Zn were the most abundant by mass fraction in PM. In EBC, the metal concentrations in decreasing order were: Zn > Cu > Ni > Ba > Mn. Security guards had the highest EBC metal concentrations, and in particular Zn and Cu. Urinary metal concentrations in decreasing order were: Si > Zn > Mo > Ti > Cu > Ba ≈ Ni > Co. All urinary metal concentrations from the subway workers were similar to concentrations found in the general population. A statistically significant relationship was found for ultrafine particle number concentrations in PM and in EBC. Zn and Cu concentrations in post-shift EBC were associated with Zn and Cu concentrations in PM10 and with post-shift urinary Zn and Cu concentrations. Therefore, EBC appears a relevant matrix for assessing exposure to UFP in human biomonitoring when inhalation is a primary route of exposure. We found different temporal variation patterns between particle and metal exposures in three matrices (PM, urine, EBC) quantified daily over two full weeks in subway workers. These patterns might be related to metal oxidation, particulates' solubility and size as well as their lung absorption capabilities, which need to be further explored in toxicological research. Further research should also focus on understanding possible influences of low chronic exposures to subway particulates on health in larger cohorts.

Respiratory Disease Occupational Biomonitoring Collaborative Project (ROBoCoP): A longitudinal pilot study and implementation research in the Parisian transport company.

The ROBoCoP project is launched within the EU COST Action CA16113 "CliniMARK" aiming to increase the number of clinically validated biomarkers and focused on chronic obstructive pulmonary disease (COPD) biomarker development and validation. ROBoCoP encompasses two consecutive studies consisting of a pilot study followed by a field study. The pilot study is a longitudinal exposure assessment and biomarker study aiming at: 1-understanding the suitability of the candidate biomarkers in surveying populations at risk such as workers exposed to COPD causing agents; 2-determining the best sampling plan with respect to the half-life of the candidate biomarkers; 3-implementing and validating the sampling procedures and analytical methods; 4-selecting the best suitable biomarkers to be measured in the field. Each study participant is surveyed every day during the 6-8 h work-shifts for two consecutive weeks. The field study has an implementation research designe that enabled us to demonstrate the applicability of the standardized protocol for biomarker measurements in occupational settings while also assessing the biomarkers' validity. ROBoCoP will focus on particulate matter (PM) exposure measurements, exposure biomarkers and a series of effect biomarkers, including markers of lipoperoxidation: 8-isoprostane, malondialdehyd in exhaled breath condensate (EBC) and urine, potential markers of nitrosative stress: NO2-, NO3- and formate anion in EBC; markers of DNA oxidation: 8-hydroxy-2'deoxyguanosine in EBC and urine, marker of genotoxicity: micronuclei in buccal cells, and oxidative potential in exhaled air (OPEA). OPEA appears particularly promising as a clinical biomarker for detecting COPD, and will be tested independently and as part of a biomarker panel. COPD diagnosis will be performed by an experienced occupational physician according to international diagnostic standards and confirmed by a pulmonologist.This research will include approximatively 300 underground subway workers randomly selected from the personnel registry of a large Parisian transport company. Underground subways are suggested as the most PM polluted urban transport environment. We believe this occupational exposure is relevant for biomonitoring of workers and early detection of respiratory diseases.

[Therapeutic education in Mali: a training workshop for caregivers and young type 1 diabetic patients]. / Éducation thérapeutique au Mali : un atelier de formation pour soignants et jeunes diabétiques de type 1.

In March 2021, in the framework of a partnership between the Geneva University Hospitals (HUG), the Santé Diabète Organization and the Ministry of Health of Mali, a 4-day workshop training course was organized with the objective of strengthening the skills of caregivers in Therapeutic Patient Education (TPE) for children and young people with type 1 diabetes. To ensure interprofessionalism, physician-nurse pairs already working together in health structures in 7 regions of Mali participated in the training. Beyond complementarity between health professionals, the aim was to cope with the realities of the Malian health system. All activities were co-chaired by physician-nurse pairs, specialized in diabetes and in TPE. A total of 30 professionals took part in the training, which consisted of 2 days of classroom training and 2 days of hands-on training with type 1 diabetic children and their families. To build the caregivers capacity in TPE, we chose innovative approaches with activities allowing the immediate application of skills learned with various pedagogical tools. The beneficiaries are not only the professionals, but also the children, teenagers and their families, including the trainers.

Access to diabetes care and treatment in Africa : challenges and opportunities.

Access to drugs is a key element in the treatment of diabetes. Access remains an issue because of their price, availability, and especially affordability. Two elements included in the sustainable development goals - universal health coverage and partnerships - offer an opportunity to improve access.

Management of type 1 diabetes.

Late diagnosis and lack of access to insulin contribute most to the mortality of people with type 1 diabetes. The presence of this chronic noncommunicable disease is not bound by borders or even continents. Without treatment, it is fatal, while with treatment and good control, it is possible to prevent acute complications (hyperglycemia and hypoglycemia) and to reduce severe late complications (cardiovascular and cerebrovascular, kidney failure and blindness). Access to equipment and supplies for diagnosis and to essential drugs for hospitals and later families at an affordable price is critical to mortality and morbidity in Africa. Intensive training of professionals in the field and in hospitals to recognize and treat this disease is necessary. These factors, together with intensive education of patients and their families, can reduce the mortality and morbidity of diabetes. Adequate management of diabetes, an important noncommunicable disease, will contribute to meeting the Sustainable Developments Goals and reducing infant mortality.

The experience of the Santé Diabète NGO in the fight against diabetes in Africa.

Several years ago, infectious diseases such as tuberculosis, HIV/AIDS, and malaria were the principal health menace on an international scale. But, today, noncommunicable diseases (NCD), such as diabetes and cardiovascular diseases, are a health emergency in both high- and low-income countries. The NGO Santé Diabète (Diabetes Health) has now been developing actions for diabetes prevention and management in Africa for 15 years. The strategies they have developed combine advocacy, support for the Ministry of Health for the implementation of plans to fight NCDs, staff training, and the establishment of a structure for prevention and management. In Mali, these activities, begun a decade ago, now manage 15,000 patients with diabetes.

[Analysis of direct medical costs of type 2 diabetes in Mali]. / Analyse des coûts médicaux directs des soins du diabète de type 2 au Mali.

BACKGROUND: Type 2 Diabetes (T2D) is rapidly increasing in Africa, but it is still rather neglected. Demonstrating the medical costs for treating type 2 diabetes would be useful for improving awareness and proposing solutions. The purpose of this study was to compare the estimated medical costs for basic chronic treatment and the actual expenditures of diabetic patients, and to identify determinants of these expenditures. METHODS: The estimated medical costs were based on price data collected from three public hospitals and their pharmacies (one university and two district hospitals), as well as from three private clinics and three private pharmacies, in Bamako. A standard treatment protocol for diabetes care, with and without complications, was first established by a working group prior to pricing of consultations, medication, care devices and specialized tests and treatments. Costs were computed using an Excel® software program. We calculated actual expenditures for medical care and examined some determinants using the data from a cross-sectional survey on 500 adult diabetic subjects in Mali. Participants were randomly selected from registries of known diabetics. RESULTS: The estimated costs for basic medical care of uncomplicated diabetes ranged from 108 to 298 € per year in the public sector, and 325 to 756 € in the private sector. Median annual expenditures of survey subjects without complications for chronic care amounted to 178 € (range: 98-331) and were therefore in the estimated range in the public sector. Total median expenditures of all survey subjects, including 78% with complications, reached 241 € per year (142-386). Additional expenditures for the treatment of complications were lower than the estimated costs, except for retinopathy. Independent predictors of higher expenditures were insulin treatment, residence in Bamako, and the number of complications. The minimum estimated cost of medical treatment for uncomplicated diabetes in the public sector represented 29% of GNP per capita. Total medical expenditures as reported by survey respondents amounted to an average of 24% of their income. CONCLUSION: Treatment of T2D is expensive and beyond reach for many patients in Mali, particularly when there are complications. Prevention of diabetes is an urgent challenge in Africa, along with early screening in order to delay and reduce the occurrence of complications.

Insulin storage in hot climates without refrigeration: temperature reduction efficacy of clay pots and other techniques.

AIM: Insulin loses potency when stored at high temperatures. Various clay pots part-filled with water, and other evaporative cooling devices, are used in less-resourced countries when home refrigeration is unavailable. This study examined the cooling efficacy of such devices. METHODS: Thirteen devices used in Sudan, Ethiopia, Tanzania, Mali, India, Pakistan and Haiti (10 clay pots, a goat skin, a vegetable gourd and a bucket filled with wet sand), and two identical commercially manufactured cooling wallets were compared. Devices were maintained according to local instructions. Internal and ambient temperature and ambient humidity were measured by electronic loggers every 5 min in Khartoum (88 h), and, for the two Malian pots, in Bamako (84 h). Cooling efficacy was assessed by average absolute temperature difference (internal vs. ambient), and % maximal possible evaporative cooling (allowing for humidity). RESULTS: During the study period, mean ambient temperature and humidity were 31.0°C and 32.0% in Khartoum and 32.9°C and 39.8% in Bamako. All devices reduced the temperature (P < 0.001) with a mean (sd) reduction from 2.7 ± 0.5°C to 8.3 ± 1.0°C, depending on the device. When expressed as % maximal cooling, device efficacy ranged from 20.5% to 71.3%. On cluster analysis, the most efficacious devices were the goat skin, two clay pots (from Ethiopia and Sudan) and the suspended cooling wallet. CONCLUSIONS: Low-cost devices used in less-resourced countries reduce storage temperatures. With more efficacious devices, average temperatures at or close to standard room temperature (20-25°C) can be achieved, even in hot climates. All devices are more efficacious at lower humidity. Further studies are needed on insulin stability to determine when these devices are necessary.

Impact of historical mining assessed in soils by kinetic extraction and lead isotopic ratios.

The aim of this study is to estimate the long-term behaviour of trace metals, in two soils differently impacted by past mining. Topsoils from two 1 km(2) zones in the forested Morvan massif (France) were sampled to assess the spatial distribution of Cd, Cu, Pb and Zn. The first zone had been contaminated by historical mining. As expected, it exhibits higher trace-metal levels and greater spatial heterogeneity than the second non-contaminated zone, supposed to represent the local background. One soil profile from each zone was investigated in detail to estimate metal behaviour, and hence, bioavailability. Kinetic extractions were performed using EDTA on three samples: the A horizon from both soil profiles and the B horizon from the contaminated soil. For all three samples, kinetic extractions can be modelled by two first-order reactions. Similar kinetic behaviour was observed for all metals, but more metal was extracted from the contaminated A horizon than from the B horizon. More surprising is the general predominance of the residual fraction over the "labile" and "less labile" pools. Past anthropogenic inputs may have percolated over time through the soil profiles because of acidic pH conditions. Stable organo-metallic complexes may also have been formed over time, reducing metal availability. These processes are not mutually exclusive. After kinetic extraction, the lead isotopic compositions of the samples exhibited different signatures, related to contamination history and intrinsic soil parameters. However, no variation in lead signature was observed during the extraction experiment, demonstrating that the "labile" and "less labile" lead pools do not differ in terms of origin. Even if trace metals resulting from past mining and metallurgy persist in soils long after these activities have ceased, kinetic extractions suggest that metals, at least for these particular forest soils, do not represent a threat for biota.

Thermodynamic and kinetic study of the single extraction of mercury from soil using sodium-thiosulfate.

The use of sodium-thiosulfate (Na-thiosulfate) as a reagent for the extraction of mercury (Hg) from soil was investigated. High organic matter content in soil plays a major role in retaining metals. It has previously been reported that using the cold vapour atomic absorption method, powerful reagents such as EDTA, DTPA and cysteine could not release Hg from soil samples. The optimal conditions for using Na-thiosulfate to extract soil-Hg are presented here. Our results show that 50±5% of total Hg was extracted from soil samples using 0.01molL(-1) of the reagent without pH adjustment. Increasing the reagent concentration above this level showed no significant change in Hg extraction. From this extraction three fractions of Hg were obtained, the labile, slowly labile and un-extractable. We further applied the use of a kinetic extraction approach that has never been applied for Hg. We observed a correlation between the first two fractions and the quantity of organic matter content in soils. The labile fraction could be released by using any concentration of the reagent. However, the slowly labile fraction was dependent on time and increased concentrations of Na-thiosulfate. Furthermore, our results suggest that the labile and slowly labile fractions involve two different sites of reduced sulphur groups contained in soil organic matter and Hg levels present in the soil samples did not appear high enough to saturate all these high affinity sulphur sites. The capacity of Na-thiosulfate to reduce (Hg(II)) to (Hg(0)), was determined to be negligible. Our results further suggest the implication of iron (Fe(II)) for reducing Hg(II) to Hg(0). Here we have demonstrated that Na-thiosulfate is an effective reagent in the extraction of Hg from soil, with the particular characteristic of its ability to remove strongly bound Hg from sulphur groups contained in soil organic matter.