Occupational Dust Exposure and Respiratory Protection of Migrant Interior Construction Workers in Two Chinese Cities.

Migrant interior construction workers are increasing in China. Construction workers are at an increased risk of work-related illness (WRI) due to prolonged exposure to and inhalation of dust. Dust concentrations in the air can be reduced significantly with effective respiratory protection measures. We assessed the dust exposure and factors associated with respiratory protection of migrant interior construction workers. The total dust concentration in the workplace ranged from 0.07 to 335.27 mg/m3, with a total dust exceedance rate of 50.00%. The respiratory dust loading ranged from 0.03 to 220.27 mg/m3, with a respiratory dust exceedance rate of 71.42 %. The highest total dust concentration occurred when masons were polishing cement walls. We performed a questionnaire survey of 296 persons in two cities in China, in which 87.84% had no respiratory protection or only one protection measure. Gender, workplace, respiratory disease, and protective attitude all had an effect on the level of respiratory protection. The dust exposure in most jobs exceeds hygiene standards. The respiratory protection of migrant interior construction workers in China is inadequate.

Occupational risk resulting from exposure to mineral wool when installing insulation in buildings.

Mineral wool is widely used for thermal and sound insulation. The subject of the study is to identify hazards for employees resulting from exposure to mineral wool, when it is used to insulate buildings, and to assess the risk arising from this exposure. When installing mineral wool insulation, respirable mineral fibers, dust, and volatile organic compounds may pose a hazard at workplaces. Based on the results of concentration measurements, it was assessed that the probability of adverse health effects related to the work of insulation installers, resulting from exposure to mineral wool fibers, is low, but for dust associated with exposure, an average health risk was estimated. An additional threat may be the sensitizing effect of substances used as binders and additives improving the utility properties of mineral wool, for example, phenol formaldehyde resins. The paper also contains some information on the labeling of mineral wool; this is very important because the label allows downstream users to recognize mineral wools, the composition and properties of which cause that they are not classified as carcinogens. Int J Occup Med Environ Health. 2020;33(6):757-69.

Changes in Spirometry Indices and Lung Cancer Mortality Risk Estimation in Concrete Workers Exposed io Crystalline Silica.

The health of workers in the concrete and cement industries can be at risk due to occupational exposure to silica dust. The purpose of this study was to evaluate the changes of pulmonary parameters and risk of mortality from lung cancer in concrete workers exposed to crystalline silica. This cross-sectional study was performed on 72 male workers exposed to silica at a concrete manufacturing plant in Neyshabur, Iran. Respiratory zone air sampling was performed using the standard NIOSH7602 method using individual sampling pumps and membrane filters. Then, the amount of silica in the samples was determined using the Fourier Transform Infrared technique. The risk of death from lung cancer was determined using Rice et al.'s model. Respiratory indices were measured using a spirometer. Data were analyzed by the SPSS 20 software. Occupational exposure to silica was 0.025 mg/m3 and mortality was estimated to be 7-94 per thousand. All spirometry indices significantly decreased during these 4 years of exposure to silica dust. The respiratory pattern of 22% of the exposed workers was obstructive and this prevalence was significantly higher than the control group. The results showed that although the average occupational exposure to silica in these concrete workers was below the recommended threshold of national and international organizations, their risk of death was significantly higher; and workers' lung indices had significantly decreased over four years. Therefore, appropriate measures should be taken to reduce silica exposure among these workers.

Construction workers' skin disorders in the Finnish Register of Occupational Diseases 2005-2016.

BACKGROUND: Construction workers are a known risk group for occupational skin disease (OSD). OBJECTIVES: To study diagnoses and causes of OSD in construction workers in the Finnish Register of Occupational Diseases (FROD) 2005-2016. MATERIALS AND METHODS: We searched the FROD for dermatological cases in (a) construction-related occupations defined by the International Standard Classification of Occupations (ISCO-08) and (b) in the industrial branch of construction defined by the Statistical Classification of Economic Activities in the European Community (NACE Rev. 2). RESULTS: The two searches yielded the same number of cases, 329, although they were not identical subgroups. The number of allergic contact dermatitis (ACD) cases was 235 (71%) in construction-related occupations and 228 (69%) in the industrial branch of construction. In the latter analysis, synthetic resin systems caused 66% of ACD cases and 46% of all OSDs, epoxy compounds being the leading cause (122 cases; 54% of ACD cases; 37% of all OSDs). Metals were the second most common group of causes of ACD with 31 cases (chrome 22 cases; cobalt 8 cases). Isothiazolinones caused ACD in 21 cases, many of whom were painters. CONCLUSIONS: ACD dominated the OSDs of construction workers and epoxy products were by far the leading cause comprising 37% of all OSDs. Chrome and isothiazolinones were also prominent causes of ACD.

Exposure-response assessment of cancer mortality in styrene-exposed boatbuilders.

OBJECTIVES: To improve exposure estimates and reexamine exposure-response relationships between cumulative styrene exposure and cancer mortality in a previously studied cohort of US boatbuilders exposed between 1959 and 1978 and followed through 2016. METHODS: Cumulative styrene exposure was estimated from work assignments and air-sampling data. Exposure-response relationships between styrene and select cancers were examined in Cox proportional hazards models matched on attained age, sex, race, birth cohort and employment duration. Models adjusted for socioeconomic status (SES). Exposures were lagged 10 years or by a period maximising the likelihood. HRs included 95% profile-likelihood CIs. Actuarial methods were used to estimate the styrene exposure corresponding to 10-4 extra lifetime risk. RESULTS: The cohort (n= 5163) contributed 201 951 person-years. Exposures were right-skewed, with mean and median of 31 and 5.7 ppm-years, respectively. Positive, monotonic exposure-response associations were evident for leukaemia (HR at 50 ppm-years styrene = 1.46; 95% CI 1.04 to 1.97) and bladder cancer (HR at 50 ppm-years styrene =1.64; 95% CI 1.14 to 2.33). There was no evidence of confounding by SES. A working lifetime exposure to 0.05 ppm styrene corresponded to one extra leukaemia death per 10 000 workers. CONCLUSIONS: The study contributes evidence of exposure-response associations between cumulative styrene exposure and cancer. Simple risk projections at current exposure levels indicate a need for formal risk assessment. Future recommendations on worker protection would benefit from additional research clarifying cancer risks from styrene exposure.

Modeling mesothelioma risk factors from amphibole fiber dimensionality: mineralogical and epidemiological perspective.

Amphiboles are common rock-forming minerals but when they form asbestos, they are known carcinogens. Mesothelioma mortality among miners and millers per the unit of asbestiform amphibole exposure varies significantly across cohorts when asbestos exposure measurements are based on the membrane filter method. Because the cohorts were exposed to different occurrences of asbestiform amphibole, variance in mesothelioma potency (RM ) among cohorts is likely due to differences in exposure characteristics not reflected by the membrane filter method. In this paper using both linear and nonlinear models we correlate RM from four mining and milling cohorts with two-dimensional parameters of the exposure. The parameters are based on the proportion of elongated minerals that are >5 µm in length from each occurrence that also have either (a) width ≤ 0.15 µm, or (b) width ≤ 0.25 µm. Based on the models we derived, it was possible to quantify RM for the occurrences of asbestiform amphibole associated with mesothelioma excess but for which epidemiologically based RM has not been published. It was demonstrated that modeled RM for amphibole occurrences in nonasbestiform habits are lower (fibrous glaucophane) or not significant (cleavage fragments). The results of the study can be used in a risk assessment of elongated mineral particles and have implications for public policy and regulations.

Colorectal cancer and asbestos exposure-an overview.

The relationship between colorectal cancer and asbestos exposure has not been fully clarified. This study aimed to determine the associations between asbestos exposure and colorectal cancer. We performed a meta-analysis to quantitatively evaluate this association. A fixed effects model was used to summarize the relative risks across studies. Sources of heterogeneity were explored through subgroup analyses and meta-regression. We analyzed the dose-effect relationship using lung cancer standardized mortality ratio (SMR) and the risk of mesothelioma as a percent (%) as exposure surrogates. A total of 47 cohort studies were included. We identified 28 incidence cohort studies from 17 separate papers and extracted colorectal cancer standardized incidence ratio (SIR). Cancer mortality data were extracted from 19 separate cohorts among 13 papers. The overall colorectal cancer SMR for synthesis cohort was 1.07 (95% CI 1.02-1.12). Statistically significant excesses were observed in exposure to mixed asbestos (SMR/SIR=1.07), exposure to production (SMR/SIR=1.11), among asbestos cement workers (SMR/SIR=1.18) and asbestos textile workers (SMR/SIR=1.11). Additionally, we determined that the SMR for lung cancer increased with increased exposure to asbestos, as did the risk for colorectal cancer. This study confirms that colorectal cancer has a positive weak associations with asbestos exposure.

[Asbestos and its effects on health of Icelanders - review].

Asbestos are crystallized silicate minerals that form fibers with different structures and characteristics. Asbestos fibers are very durable and can tolerate very high temperatures. Therefore it was common to use asbestos as a fire retardants, heat insulation and where high temperature is used. Asbestos has been banned in Iceland from 1983 but can still be found in large amounts in buildings, ships and hot water pipes. Large amounts of asbestos were imported in the years before the ban but diminished soon to almost nothing today. Needle or filamentous shaped dust is released when working with asbestos. It is this dust that is dangerous for health. The latent time from exposure to disease can be up to forty years. Asbestos reaches the lungs via inhalation and can cause asbestosis that is a form of lung fibrosis with slow progression. Asbestos can also cause benign pleural effusions, pleural plaques and diffuse pleural thickening. Asbestos is a carcinogen. Lung cancer is most common but asbestos is also a risk factor for cancers of other organs. Mesothelioma is most common in the pleura but can be seen in other membranes. The incidence of these tumors is high in Iceland and is still increasing among males. Of all the European countries mortality is highest in Iceland. It is important for physicians to include asbestos exposure in the differential diagnosis of lung diseases and when lung cancer is diagnosed.

Respiratory Problems among Workers of Udayapur Cement Factory in Eastern Nepal.

BACKGROUND: There have been very limited studies regarding health of the cement factory workers in Nepal. This study aimed to find out the prevalence of health problems and the factors associated with respiratory symptoms among the workers of Udayapur cement factory. METHODS: This is a cross-sectional study conducted from March to August 2015 in Udayapur cement factory in eastern Nepal. All the workers working in the factory more than a year were included in the study. Thedata was collected by using a semi-structured questionnaire consisting of socio-demographic characteristics,type of work, reported health problems, use of personal protective measures.Chi-square test was used to determine the association of respiratory symptoms with related variables. RESULTS: A total of 295 workers were included in this study with mean age of 45.9 years (SD=7.7). Majority 279 (94.6%) were males. The most common health problems were musculoskeletal pain (55.6%) followed by eye problems (33.2%). Among them, 17(21.1%) reported that they had at least one respiratory problem and chest tightness while running/climbing and wheeze were the most common. A total of 233 participants (79%) used at least one form of personal protective equipment. Low education, longer duration of work and smoking were found to be positively associated with respiratory symptoms. CONCLUSIONS: Respiratory problems were high among the workers of the cement factory. Proper use of PPEs and dust control measures should be promoted among the workers.

Impact of brick kilns industry on environment and human health in Pakistan.

The increase in population has led to the rise in the construction and manufacturing of bricks. Bricks are manufactured in brick kilns that emit very harmful gases which in turn affect the human health, environment and economy. In Pakistan, the diseases related to skin, and respiratory system have created a lot of problems for the humans and animals. According to experts and professionals, one of the main causes of the environment and health related problems is brick kiln. It is very important to identify the brick kilns and emissions that are extremely harmful for the environment and human health. Therefore, the objective of this research paper is threefold. Firstly, to identify and rank the emissions from brick kilns based on their harmful impact on human health and environment. Secondly, to rank the three types of brick kilns i.e. Traditional Brick Kilns (TBK) with coal as a fuel, Traditional Brick Kilns (TBK) with rubber as a fuel and Contemporary Brick Kilns (CBK) (technologically advanced brick kilns) based on their impact on human health and environment. Thirdly, to identify the relation of three alternative brick kilns with health and environmental problems, respectively. DEMATEL and Fuzzy-TOPSIS have used for achieving the objectives. The results show that CO2, CO and SO2 have the most harmful effects on the environment. Similarly, carcinogenic dioxin, SO2 and PM have the adverse effects on the human health. TBK in which rubber is used as a fuel is the most harmful and CBK is the safest types of brick kilns, respectively. In the light of the results, it is recommended to the government of Pakistan to formulate and implement the rules and regulations for minimizing the negative impacts of brick kilns on human health and environment. Moreover, new technologies should be used in order to reduce the harmful impacts.

Estimates of parameters for formaldehyde emission model from plywood panel under various temperature and relative humidity conditions.

The initial emittable concentration, Cm,0, the material phase diffusion coefficient, Dm, and the air/material partition coefficient, K, are the key parameters used to predict the formaldehyde emissions from indoor building materials. This work presents formaldehyde emission experiments of plywood panels in a climatic chamber under various environmental conditions, which provides information on how relative humidity, temperature, and loading degree affect the formaldehyde emission. The experimental results showed that formaldehyde concentration in the climatic chamber increased rapidly during the initial 3 h, and then reached equilibrium after 7 h. The equilibrium concentration of formaldehyde in the closed chamber was increased by 1.1-1.3 times with the relative humidity increased by 20%, and 1.3-2.5 times with the temperature increased by 5 °C, respectively. In agreement with the experimental treatment, a new method of estimating parameters was carried out in a theoretical model from formaldehyde emission, opening the way to a factorial analysis of the relevant parameters for relative humidity and temperature. The theoretical model with estimated parameters was further validated by experiments with different environmental conditions, which should help to quickly determine the parameters needed to predict formaldehyde emissions.

Cement plant emissions and health effects in the general population: a systematic review.

Adverse health effects of cement plant exposure have been found in occupational contexts but are less defined for the general population living near plants. We aimed to summarize the evidence on the health effects of people exposed to ambient air pollution by cement plants. A systematic review using Embase, PubMed and Web of Science was performed. We included only non-occupational studies with a comparison group that focused on adverse health outcomes and biomarkers of internal dose or subclinical effect associated with cement plant exposure. Selection of articles was performed by two authors independently. Of 1491 articles identified by the initial search, 24 were included: 17 of them were included in the analysis of adverse health outcomes and 9 in the analysis of biomarkers of internal dose or subclinical effects. The studies were very heterogeneous in study design, measure of cement plant exposure, outcome detection, measure of association and adjustment for confounding. Almost all the studies found positive associations between cement plant exposure and respiratory diseases and symptoms. An excess risk of cancer incidence and mortality in both children and adults mainly concerning respiratory tract cancers was also reported in some studies. Higher values of heavy metals and of a biomarker of renal toxicity were found in the exposed compared to unexposed populations. In conclusion, there is some evidence for a possible role of cement plant exposure on health adverse effects, although many studies had serious or critical risk of bias and overall level of certainty was low.

INVESTIGATION ON RADIATION SHIELDING PROPERTIES OF SPECIAL CONCRETE IN NEUTRON FIELDS.

This paper presents the results on radiation shielding of special types of concrete, designed for nuclear reactor containments. The research focused on the study of shielding properties against neutron component of ionizing radiation. For this purpose, two types of ionizing source were used: the isotopic reference neutron field of 239Pu-Be in calibration laboratory and the MARIA Research Reactor.

Mortality in a cohort of asbestos-exposed workers undergoing health surveillance.

BACKGROUND: The coastal area of Friuli Venezia Giulia (FVG) region, north-eastern Italy, was characterized by work activities in which asbestos was used until the early 1990s, particularly in shipbuilding. A public health surveillance program (PHSP) for asbestos-exposed workers was established, although limited evidence exists about the efficacy of such programs in reducing disease occurrence and mortality. OBJECTIVES: To compare mortality in a cohort of 2,488 men occupationally exposed to asbestos, enrolled in a PHSP in FVG between the early 1990s and 2008, with that of the general population of FVG and Italy. METHODS: Standardized Mortality Ratios (SMR), with 95% Confidence Interval (95% CI), for all causes, all cancers, lung (LC) and pleural cancer (PC) were estimated in the cohort and in subgroups of workers with the first hire in shipbuilding that caused asbestos exposure (<1974, 1974-1984, 1985-1994). RESULTS: A strong excess in mortality for PC with reference to FVG (SMR=6.87, 95% CI 4.45-10.17) and Italian population (SMR=13.95, 95% CI 9.02-20.64) was observed. For LC, the FVG-based SMR was 1.49 (95% CI 1.17-1.89) and the Italy-based 1.43 (95% CI 1.12-1.81). Mortality among workers with the first hire in shipbuilding before 1974 was high for PC (FVG-based SMR=8.98, 95% CI 5.56-13.75; Italy-based SMR=18.41, 95% CI 11.40-28.17) and for LC (FVG-based SMR =1.60, 95% CI 1.18-2.11; Italy-based SMR=1.54, 95% CI 1.14-2.03). Further, for LC between 1974 and 1984, the FVG-based SMR was 2.45 (95% CI 1.06-4.82), and the Italy-based SMR was 2.33 (95% CI 1.01-4.60). CONCLUSIONS: This cohort experienced an excess mortality for pleural and lung cancer, compared with regional and national populations. For lung cancer, the excess was stronger in workers with the first hire in shipbuilding before 1985, suggesting a key role of asbestos exposure.

Occupational exposure to asphalt mixture during road paving is related to increased mitochondria DNA copy number: a cross-sectional study.

BACKGROUND: Asphalt workers are exposed to polyaromatic hydrocarbons (PAHs) from hot mix asphalt via both inhalation and dermal absorption. The use of crumb rubber modified (CRM) asphalt may result in higher exposure to PAHs and more adverse effects. Our aim is to assess occupational exposure to PAHs from conventional and CRM asphalt paving by measuring PAH metabolites in urine, and to investigate the effects on mitochondrial DNA copy number (mtDNAcn) and telomere length. METHODS: We recruited 116 workers paving conventional asphalt, 51 workers paving CRM asphalt and 100 controls in Sweden, all males. A repeated-measures analysis included 31 workers paving both types of asphalt. Urine and blood samples were collected pre-working on Monday morning and post-working on Thursday afternoon after 4 days working. PAH metabolites: 1-hydroxypyrene (1-OH-PYR) and 2-hydroxyphenanthrene (2-OH-PH) were measured in urine by LC-MS/MS. Relative mtDNAcn and telomere length were measured by quantitative PCR. RESULTS: Conventional and CRM asphalt workers showed higher 1-OH-PYR and 2-OH-PH than controls (p < 0.001 for all). Relative mtDNAcn were 0.21 units (p < 0.001) higher in conventional asphalt workers and 0.13 units (p = 0.010) higher in CRM asphalt workers compared to controls. Relative telomere length did not differ across occupational groups, but it was positively associated with increment of 2-OH-PH (ß = 0.075, p = 0.037) in asphalt workers. The repeated-measures analysis showed no difference in either increment of 1-OH-PYP, or changes in effect biomarkers (mtDNAcn or telomere length) between paving with conventional and CRM asphalt. Increment of 2-OH-PH was smaller after paving with CRM asphalt. CONCLUSIONS: Road asphalt paving in open areas resulted in PAHs exposure, as shown by elevation of PAH metabolites in urine. Asphalt workers may experience oxidative stress, evidenced by alternation in mtDNAcn; however the effects could not be fully explained by exposure to PAHs from the asphalt mixture.

30 years follow-up and increased risks of breast cancer and leukaemia after long-term low-dose-rate radiation exposure.

BACKGROUND: The current study followed-up site-specific cancer risks in an unique cohort with 30 years' follow-up after long-term low-dose-rate radiation exposure in Taiwan. METHODS: Six thousand two hundred and forty two Taiwanese people received extra exposure in residential and school buildings constructed with Co-60-contaminated steel from 1982 until informed and relocated in early 1990s. The additional doses received have been estimated. During 1983-2012, 300 cancer cases were identified through the national cancer registry in Taiwan, 247 cases with minimum latent periods from initial exposure. The hazard ratios (HR) of site-specific cancers were estimated with additional cumulative exposure estimated individually. RESULTS: Dose-dependent risks were statistically significantly increased for leukaemia excluding chronic lymphocytic leukaemia (HR100mSv 1.18; 90% CI 1.04-1.28), breast cancers (HR100mSv 1.11; 90% CI 1.05-1.20), and all cancers (HR100mSv 1.05; 90% CI 1.0-1.08, P=0.04). Women with an initial age of exposure lower than 20 were shown with dose response increase in breast cancers risks (HR100mSv 1.38; 90% CI 1.14-1.60; P=0.0008). CONCLUSIONS: Radiation exposure before age 20 was associated with a significantly increased risk of breast cancer at much lower radiation exposure than observed previously.

Increased incidence of respiratory tract cancers in people living near Portland cement plants in Korea.

PURPOSE: Portland cement contains carcinogens such as chromium and free silica, and hence, inhalation of cement dust can cause respiratory tract cancers. The purpose of this study was to determine whether living near a cement plant increases the risk of respiratory tract cancers. METHODS: The study population consisted of 341,793 people, all of whom lived in administrative districts within 3-km radius of ten cement plants in Korea. The respiratory tract cancer incidence data (International Classification of Diseases, ten revision code C00-C14 and C30-C34) for 2008-2012 were obtained from regional cancer registries. Standardized incidence ratios (SIRs) for each cancer site in the respiratory tract were calculated using an indirect standardization method. RESULTS: Compared with the general Korean population, the incidence of lung and bronchus cancer (C33-C34) was significantly higher in all subjects [SIR 1.15, 95% confidence interval (CI) 1.02-1.29] and especially in the men subjects (SIR 1.47, 95% CI 1.29-1.68) in our study population. In addition, the incidence of larynx cancer in men (SIR 1.64, 95% CI 0.97-2.59) and salivary gland cancer in women (SIR 3.03, 95% CI 0.98-7.07) living near cement plants was marginally increased. CONCLUSIONS: These results suggest that environmental exposure to Portland cement dust is a risk factor for respiratory tract cancers.

Modeling Variables With a Spike at Zero: Examples and Practical Recommendations.

In most epidemiologic studies and in clinical research generally, there are variables with a spike at zero, namely variables for which a proportion of individuals have zero exposure (e.g., never smokers) and among those exposed the variable has a continuous distribution. Different options exist for modeling such variables, such as categorization where the nonexposed form the reference group, or ignoring the spike by including the variable in the regression model with or without some transformation or modeling procedures. It has been shown that such situations can be analyzed by adding a binary indicator (exposed/nonexposed) to the regression model, and a method based on fractional polynomials with which to estimate a suitable functional form for the positive portion of the spike-at-zero variable distribution has been developed. In this paper, we compare different approaches using data from 3 case-control studies carried out in Germany: the Mammary Carcinoma Risk Factor Investigation (MARIE), a breast cancer study conducted in 2002-2005 (Flesch-Janys et al., Int J Cancer. 2008;123(4):933-941); the Rhein-Neckar Larynx Study, a study of laryngeal cancer conducted in 1998-2000 (Dietz et al., Int J Cancer. 2004;108(6):907-911); and a lung cancer study conducted in 1988-1993 (Jöckel et al., Int J Epidemiol. 1998;27(4):549-560). Strengths and limitations of different procedures are demonstrated, and some recommendations for practical use are given.

Association between exposure in the cement production industry and non-malignant respiratory effects: a systematic review.

OBJECTIVES: Based on findings from a systematic literature search, we present and discuss the evidence for an association between exposure to cement dust and non-malignant respiratory effects in cement production workers. DESIGN AND SETTING: Systematic literature searches (MEDLINE and Embase) were performed. Outcomes were restricted to respiratory symptoms, lung function indices, asthma, chronic bronchitis, chronic obstructive pulmonary disease, pneumoconiosis, induced sputum or fraction of exhaled nitric oxide (FeNO) measurements. PARTICIPANTS: The studies included exposed cement production workers and non-exposed or low-exposed referents. PRIMARY AND SECONDARY OUTCOMES: The searches yielded 594 references, and 26 articles were included. Cross-sectional studies show reduced lung function levels at or above 4.5 mg/m3 of total dust and 2.2 mg/m3 of respiratory dust. ORs for symptoms ranged from 1.2 to 4.8, while FEV1/FVC was 1-6% lower in exposed than in controls. Cohort studies reported a high yearly decline in FEV1/FVC ranging from 0.8% to 1.7% for exposed workers. 1 longitudinal study reported airflow limitation at levels of exposure comparable to ∼1 mg/m3 respirable and 3.7-5.4 mg/m3 total dust. A dose-response relationship between exposure and decline in lung function has only been shown in 1 cohort. 2 studies have detected small increases in FeNO levels during a work shift; 1 study reported signs of airway inflammation in induced sputum, whereas another did not detect an increase in hospitalisation rates. CONCLUSIONS: Lack of power, adjustment for possible confounders and other methodological issues are limitations of many of the included studies. Hence, no firm conclusions can be drawn. There are few longitudinal data, but recent studies report a dose-response relationship between cement production dust exposure and declining lung function indicating a causal relationship, and underlining the need to reduce exposure among workers in this industry.