Trends in work-related respiratory diseases attributed to nickel, chromium and cobalt in the UK: descriptive findings from The Health and Occupation Research (THOR) network 1996-2019.

BACKGROUND: Occupational exposure to metals can be associated with respiratory diseases which can adversely affect the individual's health, finances and employment. Despite this, little is known about the incidence of these respiratory conditions over prolonged periods of time. AIMS: This study aimed to investigate the trends in the incidence of work-related respiratory diseases attributed to nickel, chromium and cobalt in the UK. METHODS: Cases of occupational respiratory diseases caused by nickel, chromium or cobalt reported to Surveillance of Work-related and Occupational Respiratory Disease (SWORD), the UK-based surveillance scheme between 1996 and 2019 (inclusive), were extracted and grouped into six 4-year time periods. Cases were characterised by causative metal exposure, occupational and industrial sector. Incidence rates diseases (adjusted for physician participation and response rate) were calculated using ONS employment data. RESULTS: Of cases reported to SWORD during the study period, 1% (173 actual cases) of respiratory problems were attributed to nickel, chromium or cobalt. Diagnoses of asthma compromised the largest proportion of diagnoses (74.4%), followed by lung cancer (8.9%) and pneumoconiosis (6.7%). Cases had a mean age of 47 years (SD 13); 93% were men. The annual incidence fell from 1.6 per million employed in the first 4-year period, to 0.2 in the most recent period. CONCLUSIONS: Over 24 years, a decline in the incidence of metal-related occupational respiratory diseases was observed in the UK. This could be attributed to improvements in working conditions which resulted in reduced metal exposure but could also be due to closure of industries that might have generated case returns.

Trends in occupational and work-related contact dermatitis attributed to nickel, chromium and cobalt in the UK: findings from The Health and Occupation Research network 1996-2019.

BACKGROUND: Occupational exposure to metals such as nickel, chromium and cobalt can be associated with contact dermatitis, which can adversely affect an individual's health, finances and employment. Despite this, little is known about the incidence of metal-related occupational contact dermatitis over prolonged periods of time. OBJECTIVES: To investigate the medically reported trends in the incidence of work-related contact dermatitis attributed to nickel, chromium and cobalt in the UK. METHODS: Incidence and trends in cases of occupational contact dermatitis caused by nickel, chromium or cobalt between 1996 and 2019 (inclusive), reported to the EPIDERM surveillance scheme, were investigated and compared with trends in the incidence of occupational contact dermatitis attributed to agents other than the aforementioned metals. A sensitivity analysis restricting the study cohort to cases attributed to only one type of metal was also conducted. RESULTS: Of all cases reported to EPIDERM during the study period, 2374 (12%) were attributed to nickel, chromium or cobalt. Cases predominantly comprised females (59%), with a mean (SD) age (males and females) of 38 (13) years. Cases were most frequently reported in manufacturing, construction, and human health and social activity industries. The most frequently reported occupations were hairdressing, and sales and retail (assistants, cashiers and checkout operators). The highest annual incidence rate of contact dermatitis was observed in females (2.60 per 100 000 persons employed per year), with the first and second peak seen in those aged 16-24 and ≥ 65 years, respectively. A statistically significant decrease in the incidence of occupational contact dermatitis attributed to metals over the study period was observed for all occupations (annual average change -6.9%, 95% confidence interval -7.8 to -5.9), with much of the decrease occurring between 1996 and 2007. Similar findings were obtained in the sensitivity analyses. CONCLUSIONS: Over a period of 24 years, there has been a statistically significant decline in the incidence of metal-related occupational contact dermatitis in the UK. This could be attributed not only to improvements in working conditions, which have reduced metal exposure, but could also be due to the closure of industries in the UK that might have generated cases of contact dermatitis owing to metal exposure.

Irritant asthma and work: cases from the UK SWORD reporting scheme from 1999 to 2018.

BACKGROUND: Acute irritant asthma is a preventable health consequence of a workplace exposure and has a number of adverse outcomes. While cases and case series are reported, little is known about the causes and incidence of this condition over prolonged periods of time. AIMS: We aimed to estimate the reported incidence of irritant asthma referred to a national reporting scheme, and how this has changed over time. METHODS: Cases of irritant asthma reported to SWORD, the UK-based Surveillance of Work-related Occupational Respiratory Diseases scheme, were grouped into four 5-year time periods from 1999 onwards. Likely causative exposures, job, work sector and incidence rates were analysed over time. RESULTS: 307 actual cases equated to 1066 estimated cases; actual cases had a mean age of 46 years (SD 17.8); 70.7% were male. The annual incidence fell from 1.98 per million employed in the first 5-year period, to 0.56 in the most recent. Eleven occupational codes were associated with six or more attributed cases, and between them accounted for 38% of all cases. Thirteen exposure categories were associated with five or more cases. These were formaldehyde (n=5), cutting oils and coolants (n=6), isocyanates (n=6), pesticides and herbicides (n=6), welding fumes (n=7), paints (n=7), solder and colophony (n=7), solvents (n=9), fuel oil, diesel and ill-defined fumes (n=10), chlorine and hypochlorites (n=15), acids (n=23), smoke (n=25) and cleaning products and sterilising agents (n=39). CONCLUSIONS: While the incidence of irritant asthma may have fallen, cases are persistently attributed to well-described causes. A persistence of cases attributed to cleaning agents was seen.

Improving trends estimates for specific work-related ill-health conditions when excess zeros are present in a voluntary health reporting scheme.

BACKGROUND: Trends in occupational disease incidence are estimated in voluntary reporting schemes such as The Health and Occupational Reporting (THOR) Network in the UK. Voluntary reporting schemes request responses even if no cases are observed to reduce uncertainty in non-response. This may result in false zeros that bias trends estimates. Analysis using zero-inflated models is unsuitable for specific health outcomes due to overestimates of the excess zeros. Here, we attempt to account for excess zeros while investigating condition-specific trends. METHODS: Zero-inflated negative binomial (ZINB) models were fitted to three THOR work-related ill health surveillance schemes Occupational Skin Disease Surveillance (437 reporters between 1996 and 2019), Occupational Physicians Reporting Activity (1094 between 1996 and 2019) and Surveillance of Work-Related and Occupational Respiratory Disease (878 between 1999 and 2019). The probability associated with a response being a false zero was estimated and applied in weighted negative binomial (wgt-NB) models fitted to specific ill-heath conditions. Three ill-health conditions from the three THOR schemes were considered; contact dermatitis, musculoskeletal and asthma, respectively. RESULTS: Wgt-NB models approximately estimated the incidence rate ratios reported by the ZINB models (eg, EPIDERM; ZINB=0.969, NB=0.963, wgt-NB=0.968) for all health outcome annual trends. This was consistent for specific health outcomes which also tended towards the null (eg, contact dermatitis; NB=0.964, wgt-NB=0.969), indicating potentially overestimated downward trends. Though as the ratio of excess zeros to true zeros decreased in rarer health outcomes, the influence on trends also decreased. CONCLUSIONS: Through weighting, we were able to adjust for excess zeros in health outcome-specific trends estimates. Though uncertainty is still present in underlying reporter behaviour meaning caution should be applied with interpretation of any results.

Occupational inhalational accidents: analysis of cases from the UK SWORD reporting scheme from 1999 to 2018.

OBJECTIVE: To estimate the reported UK incidence of occupational inhalation accidents, and to consider changes of incidence and potential causes over time. METHODS: Cases of occupational inhalation accident reported to Surveillance of Work Related Occupational Respiratory Diseases (SWORD) over 20 years were grouped into four 5-year time periods. Cases were characterised by causative exposure, occupation and industrial sector. Incidence rates were calculated using Office of National Statistics employment data. RESULTS: The 172 actual cases reported to SWORD equated to an estimated 502 cases after adjusting for reporting frequency. Their mean age was 41.3 years (SD 12.3); 77% were male. The annual incidence fell from 1.7 per million employed in the first 5-year period, to 0.5 in the most recent. The most common occupations, responsible for 35% of all cases, were in descending order (number, % of total cases): Labourers in process and plant operations (8, 4.7), welding trades (8, 4.7), fire service officers (8, 4.7), heavy goods vehicle drivers (7, 4.1), metal working production and maintenance fitters (7, 4.1), civil service administrative officers and assistants (7, 4.1), food, drink and tobacco process operatives (6, 3.5), and three summated categories of elementary and service occupations including cleaners and domestics (10, 5.8).Three of 40 exposure categories were common to all time periods; acids (19.6% of all cases 1999-2004, 2.3% 2005-2009, 6.3% 2010-2013, 6.3% 2014-2018), chlorine/hypochlorites (7.2%, 7.0%, 2.5%, 6.3%, respectively) and solvents (14.4%, 11.6%, 12.5%, 6.3%, respectively). CONCLUSIONS: The incidence of inhalation accidents appears to have fallen, although certain exposures appear to be persistently linked to cases.

Feasibility of Indonesia Family Life Survey Wave 5 (IFLS5) Data for Air Pollution Exposure-Response Study in Indonesia.

BACKGROUND: Air pollution is an important risk factor for the disease burden; however there is limited evidence in Indonesia on the effect of air pollution on health, due to lack of exposure and health outcome data. The objective of this study is to evaluate the potential use of the IFLS data for response part of urban-scale air pollution exposure-health response studies. METHODS: Relevant variables were extracted based on IFLS5 documentation review. Analysis of the spatial distribution of respondent, data completeness, prevalence of relevant health outcomes, and consistency or agreement evaluation between similar variables were performed. Power for ideal sample size was estimated. RESULTS: There were 58,304 respondents across 23 provinces, with the highest density in Jakarta (750/district). Among chronic conditions, hypertension had the highest prevalence (15-25%) with data completeness of 79-83%. Consistency among self-reported health outcome variables was 90-99%, while that with objective measurements was 42-70%. The estimated statistical power for studying air pollution effect on hypertension (prevalence = 17%) in Jakarta was approximately 0.6 (α = 0.1). CONCLUSIONS: IFLS5 data has potential use for epidemiological study of air pollution and health outcomes such as hypertension, to be coupled with high quality urban-scale air pollution exposure estimates, particularly in Jakarta.

Occupational Asthma and Its Causation in the UK Seafood Processing Industry.

OBJECTIVES: The processing of seafood (fish and shellfish) for human consumption can lead to health consequences, including occupational asthma (OA). Several non-UK studies have reported both respiratory outcomes and airborne levels of major allergens in seafood processing. However, there is a paucity of such evidence in the UK land-based seafood processing sector, which employs some 20 000 workers. METHODS: University of Manchester's Surveillance of Work-related and Occupational Respiratory Disease (SWORD) reporting system has been interrogated over the period 1992-2017 to define the incidence rate of OA cases that can be ascribed to the UK land-based processing sector, and the seafood species implicated. Airborne allergen monitoring data undertaken at Health and Safety Executive's laboratory from 2003 to 2019 have also been collated. RESULTS: The estimated annual OA incidence rate in seafood processors was 70 [95% confidence intervals (CIs) 48.9, 91.1] per 100 000 workers compared with 2.9 (95% CIs 2.8, 3.1) in 'all other industries'. The annual calculated percentage trend in OA (1992-2017) was -8.1% (95% CIs -15.9, 0.4) in seafood processing showing a similar trend to 'all other industries' (mean -7.0%; 95% CIs -7.8, -6.1). Prawns and salmon/trout were notably implicated by SWORD as causative species related to OA. There is a general paucity of available UK airborne allergen monitoring data, particularly concerning processing salmon or trout. Available airborne monitoring for salmon parvalbumin in seven processors ranged between the limit of detection and 816 ng m-3 (n = 64). Available air monitoring levels of the major shellfish allergen (tropomyosin) during processing of crabs and prawns ranged between 1 and 101 600 ng m-3 (n = 280), highlighting that high levels of exposure can occur. CONCLUSIONS: These data show an excess incidence of OA in the UK seafood processing industry during 1992-2017, with limited airborne monitoring data for the processing of prawn, crab, and salmon suggesting that significant exposure to major seafood allergens can occur in this industry. Further investigation of current levels of respiratory ill-health and the sources of allergen exposure are warranted.

Occupational and work-related respiratory disease attributed to cleaning products.

OBJECTIVES: Exposure to cleaning products has been associated with adverse respiratory outcomes. This study aimed to investigate the medically reported incidence, trends in incidence and occupational determinants of work-related respiratory disorders attributed to cleaning agents and to explore the role of 'Quantitative Structure Activity Relationships' (QSAR) in corroborating the identification of chemical respiratory sensitisers. METHODS: Respiratory diagnoses attributed to cleaning agents were extracted from The Health and Occupation Research (THOR) surveillance network, 1989-2017. Incidence, trends in incidence and incidence rate ratios by occupation were investigated. Agents were classified by chemical type and QSAR hazard indices were determined for specific organic chemicals. RESULTS: Approximately 6% (779 cases) of the (non-asbestos) THOR respiratory cases were attributed to cleaning agents. Diagnoses were predominantly asthma (58%) and inhalation accidents (27%) with frequently reported chemical categories being aldehydes (30%) and chlorine/its releasers (26%). No significant trend in asthma incidence (1999-2017) was observed (annual average change of -1.1% (95% CI -4.4 to 2.4)). This contrasted with a statistically significant annual decline in asthma incidence (-6.8% (95% CI -8.0 to -5.6)) for non-cleaning agents. There was a large variation in risk between occupations. 7 of the 15 organic chemicals specifically identified had a QSAR generated hazard index consistent with being a respiratory sensitiser. CONCLUSION: Specific occupations appear to be at increased risk of adverse respiratory outcomes attributed to cleaning agents. While exposure to agents such as glutaraldehyde have been addressed, other exposures, such as to chlorine, remain important. Chemical features of the cleaning agents helped distinguish between sensitising and irritant agents.

Emerging trends in the UK incidence of occupational asthma: should we be worried?

While 15% of adult-onset asthma is estimated to have an occupational cause, there has been evidence of a downward trend in occupational asthma incidence in several European countries since the start of this millennium. However, recent data from The Health and Occupation Reporting network in the UK have suggested a possible reversal of this downward trend since 2014. We present these data and discuss possible explanations for this observed change in incidence trend. A high index of suspicion of occupational causation in new-onset asthma cases continues to be important, whether or not the recently observed increase in occupational asthma incidence in the UK is real or artefactual.

Epidemiology of silicosis: reports from the SWORD scheme in the UK from 1996 to 2017.

OBJECTIVE: To document the demographic risk factors of workers reported to have silicosis in the UK. METHODS: All cases of silicosis reported to the Surveillance of Work-related and Occupational Respiratory Disease (SWORD) scheme between January 1996 and December 2017 were classified into one of eight industry categories, and one of five age groups. In addition, to investigate whether there had been any temporal change, mean age and range at diagnosis was plotted for each year. From 2006, data were also available relating to the date of onset of symptoms, allowing a comparison between workers with and without respiratory symptoms. RESULTS: For the period between 1996 and 2017, there were 216 cases of silicosis reported. The mean (range) age of those reported was 61 years (23-89), with the majority (98%) being male. Across all industries, 65% of cases were diagnosed in individuals of working age (<65 for men and <60 for women). Silicosis was reported in young workers across all industry groups, with around one in six of all silicosis cases affecting workers under the age of 46 years. There was no clear trend in age of diagnosis with time. Between 2006 and 2017, 81% of 108 workers with silicosis were reported to be symptomatic. CONCLUSIONS: Silicosis remains an important health problem in the UK affecting workers of all ages across a wide range of industries traditionally associated with silica exposure.

A review of non-glove personal protective equipment-related occupational dermatoses reported to EPIDERM between 1993 and 2013.

BACKGROUND: Personal protective equipment (PPE) is defined as equipment that protects the wearer's body against health/safety risks at work. Gloves cause many dermatoses. Non-glove PPE constitutes a wide array of garments. Dermatoses resulting from these have hitherto not been documented. OBJECTIVES: To determine the incidence and types of non-glove PPE-related dermatoses. PATIENTS/METHODS: We analysed incident case reports from dermatologists of non-glove PPE-related dermatoses to a UK-wide surveillance scheme (EPIDERM) between 1993 and 2013. RESULTS: The dermatoses associated with non-glove PPE accounted for 0.84% of all occupational skin disease. Of all PPE-related cases, 194 (9.2%) were attributable to non-glove PPE. Of these, 132 (68.0%) occurred in men, and the median age (both male and female) was 42 years (range 18-82 years). The non-glove PPE-related dermatoses were diagnosed as: allergic contact dermatitis (47.4%), irritant contact dermatitis (16.0%), friction (11.3%), occlusion (11.3%), unspecified dermatitis (8.8%), acne (3.1%), infections (1.5), and contact urticaria (0.52%). The industries most associated with non-glove PPE-related dermatoses were manufacturing (18.6%), public administration and defence (17.0%), health and social work (15.5%), and transport, storage, and communication (9.8%). CONCLUSIONS: Clothing, footwear, facemasks and headgear need to be recognized as causes of dermatoses occurring at body sites less commonly associated with occupational skin disease.

Burnout syndrome as an occupational disease in the European Union: an exploratory study.

The risk of psychological disorders influencing the health of workers increases in accordance with growing requirements on employees across various professions. This study aimed to compare approaches to the burnout syndrome in European countries. A questionnaire focusing on stress-related occupational diseases was distributed to national experts of 28 European Union countries. A total of 23 countries responded. In 9 countries (Denmark, Estonia, France, Hungary, Latvia, Netherlands, Portugal, Slovakia and Sweden) burnout syndrome may be acknowledged as an occupational disease. Latvia has burnout syndrome explicitly included on the List of ODs. Compensation for burnout syndrome has been awarded in Denmark, France, Latvia, Portugal and Sweden. Only in 39% of the countries a possibility to acknowledge burnout syndrome as an occupational disease exists, with most of compensated cases only occurring in recent years. New systems to collect data on suspected cases have been developed reflecting the growing recognition of the impact of the psychosocial work environment. In agreement with the EU legislation, all EU countries in the study have an action plan to prevent stress at the workplace.

UK trends of allergic occupational skin disease attributed to fragrances 1996-2015.

BACKGROUND: Fragrances are well known to cause allergic contact dermatitis (ACD). Occupationally related cases occur, with certain groups being at higher risk. OBJECTIVE: To investigate the incidence of occupationally related cases of cutaneous fragrance allergy and to evaluate trends. METHOD: Data on incident cases of occupational ACD caused by fragrances between 1996 and 2015 (inclusive) reported to the EPIDERM surveillance scheme were analysed. RESULTS: Of the cases reported to EPIDERM during the study period, 5.2% had ACD attributed to fragrances. The highest annual incidence rates were observed in women. Hairdressers, beauticians and people working in related occupations had a 47-fold higher incidence rate ratio than the reference category (the average of all other occupations combined). Trends analysis suggested a non-significant increase in fragrance allergy over the study period among all occupations, and beauty and food workers, and a slight decrease in healthcare workers. CONCLUSIONS: Fragrance allergy is a significant problem in an occupational setting. Although there was no significant change in the incidence of fragrance-related allergic occupational contact dermatitis (OCD) during the 20-year study period, this does not mirror the trend in OCD, which is falling. Fragrance allergy continues to be a major contributor to OCD, and contributes to a greater proportion of cases.

Chest physician-reported, work-related, long-latency respiratory disease in Great Britain.

Much of the current burden of long-latency respiratory disease (LLRD) in Great Britain is attributed to historical asbestos exposure. However, continuing exposure to other agents, notably silica, also contributes to disease burden. The aim of this study was to investigate the incidence of work-related LLRD reported by chest physicians in Great Britain, including variations by age, gender, occupation and suspected agent.LLRD incidence and incidence rate ratios by occupation were estimated (1996-2014). Mesothelioma cases by occupation were compared with proportional mortality ratios.Cases were predominantly in men (95%) and 92% of all cases were attributed to asbestos. Annual average incidence rates (males) per 100 000 were: benign pleural disease, 7.1 (95% CI 6.0-8.2); mesothelioma, 5.4 (4.8-6.0); pneumoconiosis, 1.9 (1.7-2.2); lung cancer, 0.8 (0.6-1.0); chronic obstructive pulmonary disease (COPD), 0.3 (0.2-0.4). Occupations with a particularly high incidence of LLRD were miners and quarrymen (COPD), plumbers and gas fitters (asbestosis), and shipyard and dock workers (all other categories). There was a clear concordance between cases of SWORD mesothelioma and proportional mortality ratios by occupation.Occupationally caused LLRD continues to contribute to a significant disease burden. Many cases are attributable to past exposure to agents such as asbestos and silica, but the potential for occupational exposures persists.

The Health and Occupation Research Network: An Evolving Surveillance System.

Vital to the prevention of work-related ill-health (WRIH) is the availability of good quality data regarding WRIH burden and risks. Physician-based surveillance systems such as The Health and Occupation Research (THOR) network in the UK are often established in response to limitations of statutory, compensation-based systems for addressing certain epidemiological aspects of disease surveillance. However, to fulfil their purpose, THOR and others need to have methodologic rigor in capturing and ascertaining cases. This article describes how data collected by THOR and analogous systems can inform WRIH incidence, trends, and other determinants. An overview of the different strands of THOR research is provided, including methodologic advancements facilitated by increased data quantity/quality over time and the value of the research outputs for informing Government and other policy makers. In doing so, the utility of data collected by systems such as THOR to address a wide range of research questions, both in relation to WRIH and to wider issues of public and social health, is demonstrated.

Work-related ill health in doctors working in Great Britain: incidence rates and trends.

BackgroundDoctors have a higher prevalence of mental ill health compared with other professional occupations but incidence rates are poorly studied.AimsTo determine incidence rates and trends of work-related ill health (WRIH) and work-related mental ill health (WRMIH) in doctors compared with other professions in Great Britain.MethodIncidence rates were calculated using an occupational physician reporting scheme from 2005-2010. Multilevel regression was use to study incidence rates from 2001 to 2014.ResultsAnnual incidence rates for WRIH and WRIMH in doctors were 515 and 431 per 100 000 people employed, respectively. Higher incidence rates for WRIH and WRMIH were observed for ambulance staff and nurses, respectively. Doctors demonstrated an annual average incidence rates increase for WRIH and WRMIH, especially in women, whereas the other occupations demonstrated a decreasing or static trend. The difference in trends between the occupations was statistically significant.ConclusionsWRIH and WRMIH incidence rate are increasing in doctors, especially in women, warranting further research.

Methylchloroisothiazolinone and methylisothiazolinone contact allergy: an occupational perspective.

BACKGROUND: Sensitivity to either methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) or MI has increased, with a reported frequency of up to 11.1% among dermatitis patients, the main context being allergic contact dermatitis caused by MCI or MCI/MI in personal care products. Case reports have described occupational allergic contact dermatitis caused by MI in paints and within the beauty industry. PATIENTS/MATERIALS/METHODS: This study identified incident cases of occupational allergic contact dermatitis caused by MCI/MI and or MI reported from 1996 to 2012 to a UK-wide surveillance scheme (EPIDERM), with the aim of identifying changes in incidence over the study period. RESULTS: The data show an increase in occupational allergic contact dermatitis caused by MCI/MI and or MI from 1996 to 2012 of 4.1% [95% confidence interval (CI) 1.6-6.9] per annum. Analysis by industry showed a 3.8% (95% CI: -0.3 to 8.0) per annum increase in those exposed to personal care products in the workplace as a primary exposure [healthcare workers, 8.1% (95% CI: 2.1-14.4) per annum; beauty workers, 6.6% (95% CI: -2.2 to 16.2) per annum; hairdressers, 1.5% (95% CI: -4.7 to 8.1) per annum]. There was a 6.3% (95% CI: 1.8-10.9) per annum increase for manufacturing workers. A statistically significant rise in the frequency of occupational allergic contact dermatitis was shown to be attributable to MCI/MI and or MI between 1996 and 2012. CONCLUSION: The findings support recommendations for a review of the regulations relating to MCI/MI and/or MI in cosmetic and personal care products and in industrial settings.

UK rates of occupational skin disease attributed to rubber accelerators, 1996-2012.

BACKGROUND: Natural and synthetic rubbers containing rubber accelerators are well-known causes of allergic contact dermatitis (ACD). Latex contact urticaria (CU) has been widely reported, especially when powdered latex glove use was commonplace. Consequently, interventions to reduce latex exposure by altering glove manufacture were introduced. OBJECTIVE: This study aimed to analyse trends in UK-reported incidence of occupational skin disease associated with rubber accelerators. METHOD: We analysed cases reported to EPIDERM (part of The Health and Occupation Research network) of occupational ACD caused by natural and synthetic rubber products, between 1996 and 2012. RESULTS: For the studied period, a decreasing incidence of ACD associated with rubber products was found, with an average annual change of -1.2% [95% confidence interval (CI) -3.1 to 0.7]. The number of cases of latex CU (n = 580) significantly declined. The number of cases of ACD caused by mercapto mix and mercaptobenzothiazole (n = 177) and thiuram mix (n = 603) also declined. Reports of ACD associated with carba mix and its constituents (n = 219) increased significantly, by an average annual percentage of 10.1% (95%CI: 6.1-14.2). Twenty-six cases of ACD caused by rarer rubber compounds were identified, highlighting skin disease attributable to less widely recognized chemicals. CONCLUSIONS: These data show a falling reported incidence of occupational ACD attributed to rubber chemicals, but within this a significant rise attributable to the constituents of the carba mix. Clinicians should recognize the changing diversity of chemicals used in rubber manufacturing, and consider including carba mix in their baseline series and testing beyond this in suspect cases to avoid false-negative results.