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Ecosystems integrity and services are threatened by anthropogenic global changes. Mitigating and adapting to these changes require knowledge of ecosystem functioning in the expected novel environments, informed in large part through experimentation and modelling. This paper describes 13 advanced controlled environment facilities for experimental ecosystem studies, herein termed ecotrons, open to the international community. Ecotrons enable simulation of a wide range of natural environmental conditions in replicated and independent experimental units while measuring various ecosystem processes. This capacity to realistically control ecosystem environments is used to emulate a variety of climatic scenarios and soil conditions, in natural sunlight or through broad‐spectrum lighting. The use of large ecosystem samples, intact or reconstructed, minimizes border effects and increases biological and physical complexity. Measurements of concentrations of greenhouse trace gases as well as their net exchange between the ecosystem and the atmosphere are performed in most ecotrons, often quasi continuously. The flow of matter is often tracked with the use of stable isotope tracers of carbon and other elements. Equipment is available for measurements of soil water status as well as root and canopy growth. The experiments ran so far emphasize the diversity of the hosted research. Half of them concern global changes, often with a manipulation of more than one driver. About a quarter deal with the impact of biodiversity loss on ecosystem functioning and one quarter with ecosystem or plant physiology. We discuss how the methodology for environmental simulation and process measurements, especially in soil, can be improved and stress the need to establish stronger links with modelling in future projects. These developments will enable further improvements in mechanistic understanding and predictive capacity of ecotron research which will play, in complementarity with field experimentation and monitoring, a crucial role in exploring the ecosystem consequences of environmental changes., Experimentation and modelling are necessary to predict ecosystem functioning under future environments and to develop mitigating and adapting strategies. This paper describes 13 advanced controlled environment facilities, called ecotrons, open to the international community. An ecotron comprises a set of replicated enclosures designed to host ecosystems samples and enable realistic simulations of above‐ and belowground environmental conditions, while simultaneously and automatically measuring ecosystem processes. The characteristics of these infrastructures are given as well as examples of collaborative projects hosted so far.

BackgroundData on the effects of extremely low frequency electromagnetic fields (ELF-EMF) on pregnancy outcomes are inconclusive.ObjectiveTo study the relation between maternal cumulative exposure to ELF-EMF during pregnancy and the risk of prematurity or small for gestational age (SGA) in a pooled analysis of two French birth cohorts.MethodsElfe and Epipage2 are both population-based birth cohorts initiated in 2011 and included 18 329 and 8400 births, respectively. Health data and household, mother and child characteristics were obtained from medical records and questionnaires at maternity and during follow-up. A job exposure matrix was used to assess cumulative exposure to ELF-EMF during three periods: (1) until 15 weeks of gestation, (2) until 28 weeks of gestation and (3) until 32 weeks of gestation. Analyses were restricted to single live births in mainland France and to mothers with documented jobs (N=19 894). Adjusted logistic regression models were used.ResultsAccording to the period studied, 3.2%–4% of mothers were classified as highly exposed. Results were heterogeneous. Increased risks of prematurity were found among low exposed mothers for the three periods, and no association was observed among the most exposed (OR1=0.92 (95% CI 0.74 to 1.15); OR2=0.98 (95% CI 0.80 to 1.21); OR3=1.14 (95% CI 0.92 to 1.41)). For SGA, no association was observed with the exception of increased risk among the low exposed mothers in period 2 and the most exposed in period 3 (OR=1.25 (95% CI 1.02 to 1.53)).ConclusionSome heterogeneous associations between ELF-EMF exposure and prematurity and SGA were observed. However, due to heterogeneity (ie, their independence regarding the level of exposure), associations cannot be definitely explained by ELF-EMF exposure.

International audience; Background:Pesticide exposures are suspected to be implicated in the excess of central nervous system (CNS) tumours observed in farmers, but evidence concerning individual pesticides remains limited. Carbamate insecticides, used on a wide range of crops, have shown evidence of carcinogenicity in some experimental studies. In the cohort AGRICAN (AGRIculture & CANcer), we assessed the associations between potential exposures to carbamate insecticides and the incidence of CNS tumours, overall and by histological subtype.Methods:AGRICAN enrolled 181 842 participants involved in agriculture. Incident CNS tumours were identified by linkage with cancer registries from enrolment (2005-07) until 2013. Carbamate exposure was assessed by combining information on lifetime periods of pesticide use on crop or livestock and the French crop-exposure matrix PESTIMAT, individually for each of the 19 carbamate insecticides registered in France since 1950. Associations were estimated using proportional hazards models with age as the underlying time scale, adjusting for gender, educational level and smoking.Results:During a 6.9-year average follow-up, 381 incident cases of CNS tumours occurred, including 164 gliomas and 134 meningiomas. Analyses showed increased risks of CNS tumours with overall exposure to carbamate insecticides and linear trends with duration of use of each carbamate. Considering tumour subtypes, hazard ratios for gliomas ranged from 1.18 for thiofanox to 4.60 for formetanate, and for meningiomas from 1.51 for carbaryl to 3.67 for thiofanox.Conclusions:Findings reinforce carcinogenicity evidence for already suspected active ingredients and draw attention to additional active ingredients, notably used on fruit trees, vineyards, potatoes and beets.

International audience; PURPOSE:Epidemiological studies have found an increased risk of multiple myeloma (MM) in farmers. Few studies have investigated the detailed circumstances of occupational pesticide exposure which could explain these increased risks (pesticide use on crops, seeds or on animals, contact with treated crops) and the role of other exposures. In the Agriculture and Cancer cohort (AGRICAN), we assessed the associations between MM and crop- or animal-related activities, with specific attention to pesticide exposure via use on animals and crops or contact with treated crops and to disinfectant exposure.METHODS:Analyses concerned 155,192 participants, including 269 incident MM identified by cancer registries from enrolment (2005-2007) to 2013. Cox models using attained age as time scale were run to calculate hazard ratios (HR) and 95% confidence intervals (CI).RESULTS:MM risk was increased in farmers (i) who started using pesticides on crops in the 1960s, especially among those applying pesticides on corn (≥ 20 years: HR 1.73, 95% CI 1.08, 2.78, p for trend

International audience; Occupational exposure to pesticides concerns a wide population of workers not only in agriculture. The reliability of self-reported information on pesticide use is questionable because of the diversity of use. The PESTIPOP job-exposure matrix has been designed to assess pesticide occupational exposure in the general population. The matrix is composed of two axes: the first axis corresponding to jobs (combinations of occupations and industries) and the second one to pesticide exposure. The estimated exposure metric is the probability of exposure coupled with a reliability assessment (low, medium or high). These metrics were defined by combining different sources: (1) an a priori expert assessment (Agricultural industry experts); (2) data from a multicenter case-control study on brain tumors in the general population (occupational history, specific questionnaires); and (3) an a posteriori expert assessment based on the data of a case-control study. So far, 2559 jobs have been identified and 209 (8%) were found to be exposed to pesticides. Jobs with agricultural exposure had a higher exposure probability than jobs with non-agricultural exposure (wood preservation, park maintenance, pest control). Indirect exposure was more frequent than direct exposure. The PESTIPOP matrix will be transcoded into international classifications for use in epidemiological studies.

Studies in farmers suggest a possible role of pesticides in the occurrence of Central Nervous System (CNS) tumors but scientific evidence is still insufficient. Using data from the French prospective agricultural cohort AGRICAN (Agriculture & Cancer), we investigated the associations between exposure of farmers and pesticide users to various kinds of crops and animal farming and the incidence of CNS tumors, overall and by subtypes. Over the 2005-2007, 181,842 participants completed the enrollment questionnaire that collected a complete job calendar with lifetime history of farming types. Associations were estimated using proportional hazards models with age as underlying timescale. During a 5.2 years average follow-up, 273 incident cases of CNS tumors occurred, including 126 gliomas and 87 meningiomas. Analyses showed several increased risks of CNS tumors in farmers, especially in pesticide users (hazard ratio = 1.96; 95% confidence interval: 1.11-3.47). Associations varied with tumor subtypes and kinds of crop and animal farming. The main increases in risk were observed for meningiomas in pig farmers and in farmers growing sunflowers, beets and potatoes and for gliomas in farmers growing grasslands. In most cases, more pronounced risk excesses were observed among pesticide applicators. Even if we cannot completely rule out the contribution of other factors, pesticide exposures could be of primary concern to explain these findings.

ObjectivesFarmers are considered at lower risk of lung cancer. However, specific tasks can expose them to hazardous air contaminants such as pesticides, diesel exhaust and mineral dust. This study aimed to assess the associations between various crops and related tasks and the risk of lung cancer, overall and by histological subtypes.MethodsAGRIculture and CANcer is a prospective French cohort of individuals affiliated to the agricultural health insurance scheme. Incident lung cancers (n=897) were identified by cancer registries from enrolment (2005–2007) to 2013. Data on crop and livestock exposure during lifetime were obtained from the enrolment questionnaire. We used a Cox model with attained age as timescale, adjusted for gender, smoking history and exposure to cattle and horses. Effects of duration and surface were assessed and analyses stratified on gender and smoking status were performed.ResultsWinegrowers were at higher risk of adenocarcinoma (HR=1.27 (95% CI 0.94 to 1.72)). We also found an association between pea growing and small cell lung cancer: significant effect of duration (ptrend=0.04) and the suggestion of a surface–effect relationship (ptrend=0.06); increased risk (HR=2.38 (95% CI 1.07 to 5.28)) for pesticide users; and significant effect of duration (ptrend=0.01) for harvesters. The risk of squamous cell carcinoma was increased for sunflower growing (HR=1.59 (95% CI 0.97 to 2.62), fruit-tree pruning (HR=1.44 (95% CI 0.92 to 2.27)) and pesticide use on beets (HR=1.47 (95% CI 0.92 to 2.34)). Corn and/or wheat/barley growers were at lower risk of lung cancer.ConclusionsOur results suggest associations between lung cancer and several crop-related tasks, even if we cannot rule out some chance findings due to multiple comparisons.

International audience; Inverse association between allergic conditions and glioma risk has been consistently reported in epidemiological studies with little attention paid to potential environmental confounders; the association with meningioma risk is less consistent. We examined the association between allergy history and risk of glioma and meningioma in adults using data from the CERENAT (CEREbral tumors: a NATional study) multicenter case-control study carried out in 4 areas in France in 2004-2010. Participants' histories of doctor-diagnosed allergic asthma, eczema, rhinitis/hay fever and other allergic conditions were collected at onset through a detailed questionnaire delivered in a face-to-face interview. Conditional logistic regression for matched sets was adjusted for participants' educational level and mobile phone use. A total of 273 glioma cases, 218 meningioma cases and 982 matched controls selected from the local electoral rolls were analyzed. A significant inverse association was found between glioma and a history of any allergy (OR 0.52, 95% CI 0.36-0.75), with a dose-effect relationship with the number of allergic conditions reported (p-trend = 0.001) and a particularly strong association with hay fever/allergic rhinitis (OR 0.46, 95% CI 0.30-0.72). Interestingly, associations with glioma risk were more pronounced in women. For meningioma, no association was observed with overall or specific allergic conditions. Our findings confirmed the inverse association between allergic conditions and glioma risk but questioned the role of allergy in meningioma risk. Future research is needed to clarify the biological mechanism of overall allergy and allergic rhinitis on glioma and to confirm the different effect by gender.

Objectives: To study the relations between maternal cumulative exposure to extremely low frequency electromagnetic fields (ELF EMF) and the risk of moderate prematurity and small for gestational age within the Elfe cohort. Methods: The Elfe study included 18,329 infants born at 33weeks of gestation or more in France in 2011 and was designed to follow the children until 20years of age. Gestational age and anthropometric data at birth were collected in medical records and small for gestational age was defined according to a French customized growth standard. During interviews, mothers were asked to report their job status during pregnancy. If employed, their occupation was coded according to the International Standard Classification of Occupations 1988 and the date on which they stopped their work was recorded. Cumulative exposure to ELF EMF during pregnancy was assessed, for both mothers who worked and those who did not during pregnancy, using a recently-updated job-exposure matrix (JEM). Cumulative exposure was considered as a categorical variable (

Objectives To study the relations between maternal cumulative exposure to extremely low frequency electromagnetic fields (ELF MF) and the risk of moderate prematurity and small for gestational age within the birth cohort Elfe. Methods The Elfe study included 18,329 infants born at 33 weeks of amenorrhea or more in France in 2011 and was designed to follow children until 20 years of age. Gestational age and anthropometric data at birth was collected in medical records and small for gestational age was defined according to a French customised growth standard. During interviews, mothers were asked to report their job status during pregnancy. If employed, their occupation was coded according to the ISCO-88 classification and the date on which they stopped their work was recorded. Cumulative exposure to ELF MF during pregnancy was assessed, for both mothers who worked and those who didn’t work during pregnancy, using a recently updated job-exposure matrix (JEM). Cumulative exposure was considered as a categorical variable ( Results Cumulative exposure was obtained for 96.0% of the mothers. Among them, 37.5% were classified in the 23.8–36.2 µT-days category, but high exposures were rare: 1.3% in the ≥61.6 µT-days category and 5.5% in the ≥44.1 µT-days category. No significant association was observed between maternal cumulative exposure and moderate prematurity and small for gestational age. Conclusion This large population-based study does not suggest that maternal exposure to ELF MF during pregnancy is highly associated with risk of moderate prematurity or small for gestational age.

Background Studies in farmers suggest a possible role of pesticides in the occurrence of Central Nervous System (CNS) tumours. However, scientific evidences are still insufficient because of methodological limits such as study designs, sample sizes or exposure assessments. We aimed to study the associations between occupational exposures to a range of farming activities and the incidence of primary CNS tumours, globally and by subtiles. Methods In the French prospective agricultural cohort AGRICAN, 181,842 participants completed the enrollment questionnaire over the period 2005–2011. Associations between exposures to 13 crops and 5 livestock and the risks of CNS tumours (identified through linkage to cancer registries) were estimated using Cox models with age as underlying timescale, adjusted on gender, professional status and educational level. Effects of specific tasks, duration and periods of exposure were also assessed. Results During a follow-up of 5.2 years in average, 273 incident cases of CNS tumours occurred, including 126 gliomas and 87 meningiomas. Analyses showed increased risks of CNS tumours that ranged from 10% to 85% with 11 of the 13 crops, significant in farmers growing peas and beets. Concerning gliomas, increases in risk were seen for all agricultural activities. A significant risk excess was observed in pesticide users (HR = 1.73; 95% CI: 1.05–2.84), especially in vine-growers performing treatments (HR = 1.86; 95% CI: 1.06–3.26). For meningiomas, significant positive associations were observed in sunflower growers, beet growers and hog raisers. A three-fold increased risk was seen in farmers using pesticides on potatoes (HR = 2.93; 95% CI: 1.15–7.47). Conclusion In the largest prospective agricultural cohort, we observed increased risks of CNS tumours among farmers. Even if we cannot completely rule out the contribution of other agricultural factors, pesticide exposures are our main hypothesis to explain these findings. Further analyses will explore the effects of some specific pesticides using the crop-exposure matrix PESTIMAT.

Background and Aim Epidemiological studies have reported an increased risk of Parkinson's disease (PD) in farmers exposed to pesticides, but no clear conclusion can be drawn on the type of pesticide and duration of use associated with an effect. In the French agricultural cohort AGRICAN, we assessed associations between PD and pesticide use according to the types of livestock and crops grown, including exposure to some active ingredients with duration of use. Methods Self-reported PD and history of lifetime exposure to 13 crops and 5 types of animals and pesticide use were collected at enrolment (2005-07) among 181 842 participants. Exposure to selected active ingredients and duration of use lifelong were assessed with the crop-exposure matrix PESTIMAT. Associations between pesticide use and PD were estimated by logistic regression according to crops and livestock, adjusted for sex, age, educational level, smoking status and alcohol consumption. Results PD was reported by 1732 subjects (1.2%) at enrolment in the cohort. Pesticide use lifelong was associated with an increased risk of PD in all types of activities [odds ratio (OR) = 1.31 (cattle) to 1.79 (peas), P

ContextExposure to inorganic arsenicals, including occupational use of pesticides, is carcinogenic to the lung (IARC group 1). However epidemiological data are scarce for agricultural exposures. This work assesses lung cancer (LC) risk, including duration-effect relationships, associated to arsenicals use in farming, by gender and histology.MethodsWe linked data from two French projects: (1) the Agriculture and Cancer (AGRICAN) cohort, a large prospective cohort of farmers and people affiliated to the French agricultural insurance scheme and (2) the Pesticide Matrix (PESTIMAT), a crop-exposure matrix. Incident lung cancer cases were collected and their histological subtype ascertained from cancer registries, from enrolment (2005–2007) to December 31 st 2013. The enrolment questionnaire included items on smoking history, and the involvement in 18 different breedings/crops and specific tasks, including pesticide application, with years of beginning and end. We performed Cox models, with age as timescale, adjusted on gender, smoking, and two activities found to be protective in previous analyses – cattle breeding and corn growing. The reference group included farmers having never applied any pesticide on any crop. We assessed risks for each inorganic compound (lead, sodium, aluminum, copper and calcium arsenate) and for overall exposure.ResultsNearly 10% (n=14 359 people) of the population was potentially exposed to arsenicals, in vineyard growing before 2001, or in fruit-tree or potato growing before 1973. We observed 98 incident LC among exposed people. Only women exhibited a higher risk of LC (HR 3.14 95% CI(1.42–6.96) for exposure to any compound, n=7 exposed cases, all adenocarcinomas), but with no duration-effect relationship. Risks were significantly elevated for lead, copper and sodium arsenate.ConclusionWe found an increased risk of LC, especially adenocarcinomas, among women. At this stage, exposure assessment was broad: the use of an exposure index, based on probability, frequency and intensity of use, will help refine the analyses.

BackgroundData on the effects of extremely low frequency electromagnetic fields (ELF-EMF) on pregnancy outcomes are inconclusive.ObjectivesTo study the relation between maternal cumulative exposure to ELF-EMF during pregnancy and the risk of prematurity or small for gestational age in a pooled analysis of two French birth cohorts.MethodsElfe and Epipage2 are both population-based birth cohorts initiated in 2011 and included 18 329 and 8400 births respectively. Health data and household, mother and child characteristics were obtained from medical records, by face-to-face interview at maternity, and completed during follow-up. A recently updated job-exposure-matrix (JEM) was used to assess cumulative exposure to ELF-EMF during three periods: 1) until 15, 2) until 28 and 3) until 32 weeks of gestation. Analyses were restricted to single live births in mainland France and to mothers with documented jobs (n=19,894). Differences in selection frame between the two cohorts were controlled using a propensity score weighting method. We used multiple imputation method to deal with missing data. Logistic regression models adjusted for the main potential confounders were used.ResultsAccording to the period studied, 3.2% to 4% of mothers were classified as highly exposed to ELF-EMF. An increased risk of spontaneous prematurity was observed among the most exposed groups in period 2 and period 3. Overall, no consistent association with small for gestational age was found.ConclusionThis study, with substantial statistical power provides evidence of a possible association between cumulative exposure to ELF-EMF during pregnancy and the risk of spontaneous prematurity.

BackgroundPesticide exposures are suspected to be implicated in the excess of Central Nervous System (CNS) tumors observed in farmers, but evidence concerning individual pesticides remains limited. Carbamate insecticides, used on a wide range of crops, have shown evidence of carcinogenicity in some experimental studies. In the cohort AGRICAN (AGRIculture and CANcer), we assessed the associations between potential exposures to carbamate insecticides and the incidence of CNS tumors, overall and by histological subtype.MethodsAGRICAN enrolled 181 842 participants involved in agriculture. Incident CNS tumors were identified by linkage with cancer registries from enrolment (2005–2007) until 2013. Carbamate exposure was assessed by combining information on lifetime periods of pesticide use on crop or livestock and the French crop-exposure matrix PESTIMAT, individually for each of the 19 carbamate insecticides registered in France since 1950. Associations were estimated using proportional hazards models with age as the underlying timescale, adjusting for gender, educational level and smoking.ResultsDuring a 6.9 year average follow-up, 381 incident cases of CNS tumors occurred, including 164 gliomas and 134 meningiomas. Analyses showed increased risks of CNS tumors with overall exposure to carbamate insecticides and linear trends with duration of use of each carbamate. Considering tumor subtypes, hazard ratios for gliomas ranged from 1.18 for thiofanox to 4.60 for formetanate and for meningiomas from 1.51 for carbaryl to 3.67 for thiofanox.ConclusionsFindings reinforce carcinogenicity evidence for already suspected active ingredients and draw attention to additional active ingredients, notably used on fruit trees, vineyards, potatoes and beets.

PurposeIncreased risks of Non-Hodgkin’s Lymphomas (NHLs) have been reported among farmers in several meta-analyses, with exposure to pesticides as the main explanation. Few studies investigated associations by NHL subtypes and considering specific pesticides. From the French agricultural cohort AGRICAN, we assessed the role of benzimidazole fungicides use on NHL risk, overall and for multiple myeloma (MM), Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL-SLL) and Diffuse Large B-cell Lymphoma (DLBCL).MethodsNearly 1 82 000 participants affiliated in a health assurance system reported in the enrollment questionnaire (2005–2007) lifetime pesticide use with start and end year on 13 crops and were followed until 2013. Using the crop-exposure matrix PESTIMAT, associations between NHLs and benzimidazole fungicides exposure (overall and for benomyl, carbendazim, fenzaflore, thiabendazole and thiophanate methyl) were estimated using Cox models.ResultsAfter exclusion of prevalent cases, individuals with incomplete agricultural profession history data or a zero tracking period, 1,133 NHL incident cases were identified from cancer registries (269 MM, 244 CLL-SLL, 190 DLBCL). Nearly 20% of participants were considered exposed (median duration from 7 to 20 years according to active ingredient). Increased NHL risk was observed with exposure to benzimidazole, overall, on any crops (NHL: HR=1.13, 95%CI=0.94–1.37, 150 cases, no duration relationship). Moreover, borderline positive associations were reported on specific crops: wheat/barley (NHL: HR=1.23, CLL-SLL: HR=1.42), beets (DLBCL, HR=2.19) and rape (DLBCL, 2.32). Significant increased risks were reported with MM for use of thiophanate-methyl on wheat/barley (HR=3.46, 23 exposed cases, no duration relationship) and with DLBCL for all 4 benzimidazole used on beets (HR from 2.34 to 2.57 and for the 2 used on rape (HR=2.39 and 2.46), although based on respectively 7 and 6 cases.ConclusionThese findings suggest positive associations between incidence of specific NHL subtypes, and exposure to benzimidazole as a chemical family or specific ingredients in this family.

Epidemiological studies have reported an increased risk of Parkinson’s disease (PD) in farmers, especially in those exposed to pesticides, but no clear conclusion can be drawn on the type of use, duration or latency associated with an effect. In the French prospective agricultural cohort AGRICAN, we assessed associations between agricultural and pesticide exposures, including their duration, and the risk of PD. Self-reported doctor-diagnosed PD and history of life-time exposure to 13 crops and 5 types of animals and pesticide use were collected at enrollment (2005–2011) among 181,842 participants affiliated to the French agriculture health assurance scheme (77% having worked on a farm, 23% who did not). Associations between agricultural/pesticide use and PD were estimated by logistic regression adjusted for sex, age, education, smoking status and alcohol consumption. PD was reported by 1 732 subjects (1.2%). Significant higher risk of PD was found for 3 types of animals (swine, horses, and poultry) and 7 crops (corn, peas, beet, rape, fruit-growing, potatoes and vegetables): odds ratios [OR] = 1.19 (horses) to 1.46 (peas). Pesticide exposure (E) was significantly associated with PD in all the animals and crops studied except tobacco (OR = 1.31 (cattle) to 1.83 (horses)) with a significant dose related-relationship with duration of exposure on cattle, swine, horses, poultry, vineyards and rape (P-trend

Background Despite the widespread and increasing use of electricity in working environments, occupational exposure to ELF-EMF during pregnancy has been rarely documented and was often assessed using the mothers’ self-report. Our first aim was to assess maternal occupational exposure to ELF-EMF during pregnancy in the birth cohort study Elfe. Secondly, we studied the link between this exposure and child’s gestational age or birth-weight. Methods The Elfe study was initiated in 2011 in France and enrolled more than 18,000 infants born between 33 and 42 weeks’ gestation. Mother’s job title was collected by a face-to-face interview and coded using the International Standard „Classification of Occupation 1968 (ISCO68). The Bowman population-based job exposure matrix (JEM) was used to assess arithmetic-mean-workday ELF-EMF exposure level associated to the occupation held by each mother during pregnancy, expressed in µT/day. This JEM used the Standard Occupational Classification system 1980 (SOC80). ISCO68 codes were translated to their SOC80 equivalent. Exposure levels were categorised according to quartiles and 90th percentile. Multiple linear regression models were used to estimate adjusted differences in mean birth-weight and mean gestational age between exposure groups. Results A total of 13,340 mothers worked during their pregnancy. Job was coded into SOC80 for 12,671 mothers and mean-workday level was defined for 12,549. Adjusted models did not show differences between any of the exposure groups and the reference category for both birth-weight and gestational age among children born at 33 weeks’ gestation or more. Conclusion Our study, in a large birth cohort, is the first to assess maternal occupational exposure during pregnancy using a JEM based on industrial hygiene measurements. Our next aim will be to use the INTEROCC ELF-JEM (http://www.crealradiation.com), an updated version of the Bowman ELF-JEM. We will also assess environmental exposure to ELF-EMF during pregnancy and its possible association with birth outcomes.