Retrospective assessment of occupational disease trends in Russian Arctic apatite miners

Figures & data

Figure 1. Location of Khibiny apatite-nepheline deposits on the Kola Peninsula, Russia (Available at: https://www.maps-of-the-world.ru/europe/russia/large-scale-administrative-divisions-map-of-russia-2009).

Table 1. Non-occupational diseases in underground apatite miners according to annual health screening in 2007

Disease category	Cases (%)
Diseases of the musculoskeletal system and connective tissue	2 332 (34.4)
Diseases of the eye and its adnexa	1 084 (16.0)
Diseases of the circulatory system	964 (14.2)
Diseases of the respiratory system	540 (8.0)
Diseases of the digestive system	480 (7.1)
Endocrine, nutritional and metabolic diseases	244 (3.6)
Diseases of the skin and subcutaneous tissue	70 (1.0)
Diseases of the genitourinary system	196 (2.9)
Diseases of the nervous system	254 (3.7)
Neoplasms	136 (2.0)
Certain infectious and parasitic diseases	110(1.6)
Diseases of the ear and mastoid process	186 (2.7)
Injury, poisoning and certain other consequences of external causes	118 (1.7)
Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified	36 (0.5)
Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism	28 (0.4)

Figure 2. The ratio (%) between the number of workers with newly diagnosed occupational diseases and the total number of workers in the cohort in 2008–2020.

Table 2. General characteristics of newly diagnosed occupational diseases in underground apatite miners

Indicator	Cases (%)
Disease category
Diseases of the musculoskeletal system and connective tissue	270 (47.2)
Injury, poisoning and certain other consequences of external causes	119 (20.8)
Diseases of the nervous system	95 (16.6)
Diseases of the ear and mastoid process	77 (13.5)
Diseases of the respiratory system	11 (1.9)
Most prevalent nosological forms
Effects of vibration	112 (19.6)
Radiculopathy	110 (19.2)
Osteoarthritis deformans	89 (15.6)
Mono- and polyneuropathies	79 (13.8)
Noise effects on inner ear	77 (13.5)
Epicondylitis of the humerus	35 (6.1)
Myofibrosis of the forearms	27 (4.7)
Casual factors
Heavy physical work	347 (60.7)
Noise	77 (13.5)
Whole-body vibration	70 (12.2)
Hand-arm vibration	58 (10.1)
Chemicals of I–IV hazard classes	18 (3.1)
Fibrogenic aerosols	2 (0.3)
Casual circumstances
Imperfection of technological processes	362 (63.3)
Imperfection of workplaces	133 (23.2)
Design flaws of machines, mechanisms and other equipment	72 (12.6)
Breach of technological regulations	3 (0.5)
Breach of safety regulations	2 (0.3)
Total class of working conditions
Permissible (class 2)	4 (0.7)
Harmful (class 3.1)	56(9.7)
Harmful (class 3.2)	362 (63.3)
Harmful (class 3.3)	105 (18.4)
Harmful (class 3.4)	38 (6.6)
Extreme (class 4)	7 (1.2)

Table 3. Characteristics of occupational diseases in underground apatite miners of various trades in 2008–2020

Indicator	Blaster	Tunneller	Loader operator	Locomotive driver	Driller	Timber-man	Underground miner	Vibro-loading machine operator	Electric and gas welder
Total number of employees	190	85	158	223	98	68	173	37	150
Number (%) of employees with occupational diseases	52(27.4%)	43(50.6%)	39(24.7%)	42(18.8%)	33(33.7%)	22(32.4%)	12(10.8%)	11(29.7%)	6(4.0%)
Mean age ± SEM at detection of occupational disease, years	53.9±0.6	46.3±0.8	50.6±0.7	54.7±0.7	50.1±0.7	53.3±0.7	52.1±2.4	52.3±1.1	54.9±1.5
Minimum age at detection of occupational disease, years	38	34	37	37	43	45	35	44	50
Mean ± SEM experience at detection of occupational disease, years	28.0±0.7	20.4±0.7	24.8±0.8	26.1±1.0	25.1±0.8	25.7±1.0	24.2±2.2	27.0±1.4	29.9±1.9
Minimum experience at detection of occupational disease, years	12	10	15	11	12	13	15	14	24
Number of diseases	126	79	80	60	69	54	18	18	10
Number of diseases per year per 10,000 employees	510.1	714.9	389.5	207.0	541.6	610.9	88.9	374.2	51.3

In the line “Number of employees with occupational disease” % means the proportion of workers with occupational diseases in the total number of workers in this trade.

Table 4. Pairwise comparison of occupational disease risks in miners of nine trades

Indicator	Tunneller	Timber-man	Vibro-loading machine operator	Driller	Blaster	Loader operator	Locomotive driver	Underground miner	Electric and gas welder
Tunneller	-	1.56 0.017	1.67 0.034	1.51 0.031	2.12 <0.001	2.05 <0.001	2.69 <0.001	7.29 <0.001	12.65 <0.001
Timber-man	0.64 0.017	-	1.09 0.783	0.96 0.859	1.18 0.436	1.31 0.234	1.72 0.019	4.88 <0.001	8.09 <0.001
Vibro-loading machine operator	0.59 0.034	0.92 0.783	-	0.88 0.664	1.09 0.770	1.20 0.528	1.58 0.128	4.29 <0.001	7.43 <0.001
Driller	0.67 0.031	1.04 0.859	1.13 0.664	-	1.23 0.267	1.36 0.121	1.79 0.004	4.85 <0.001	8.42 <0.001
Blaster	0.54 <0.001	0.85 0.436	0.92 0.770	0.81 0.267	-	1.11 0.571	1.40 0.070	3.72 <0.001	6.45 <0.001
Loader operator	0.49 <0.001	0.76 0.234	0.83 0.528	0.73 0.030	0.90 0.571	-	1.31 0.170	3.28 <0.001	6.17 <0.001
Locomotive driver	0.58 <0.001	0.51 0.019	0.63 0.128	0.56 0.004	0.71 0.070	0.76 0.170	-	2.65 0.001	4.60 <0.001
Underground miner	0.14 <0.001	0.21 <0.001	0.23 <0.001	0.21 <0.001	0.27 <0.001	0.30 <0.001	0.38 0.001	-	1.73 0.252
Electric and gas welder	0.07 <0.001	0.12 <0.00	0.13 <0.001	0.12 <0.001	0.16 <0.001	0.16 <0.001	0.22 <0.001	0.58 0.252	-

Upper line – the relative risk values; Bottom line – p-values (significance level).