Table 1

- Characteristics of the included studies in terms of number of patients,method of diagnosis and exposure to environmental and occupational factors.

Reference/year	Number of patients	Diagnosis methods	Occupation and environmental exposure
Gao et la,¹ 2016	851	Diagnosis based on EPOS¹	Clearance-related job (32 patients with CRS), poisonous gases (58), animal fur and having pets at home (154), carpet at home or in the workplace (51 patients with CRS),² air conditioner (439 patients with CRS who exposed to air conditioning less than 3 days/week, and 208 patients who exposed 3-6 days/week, and 129 CRS patients who exposed to air conditioning everyday), exposure to mould or damp environments (45 for CRS patients who exposed everyday, 137 who exposed frequently)
Homood et al,³ 2017	219	Diagnosis based on a survey that included 20 questions to investigate the sociodemographic and risk factors of chronic sinusitis. Criteria for patient selection was not mentioned	Smoking (34 patients having sinusitis), injury exposure (185 having sinusitis), nasal deformities (29), exposure to pollution(34), immune system disturbance (15), aspirin sensitivity (7), allergy (151), bronchial asthma (28), medical and non-medical jobs
Hussein et al,⁵ 2019	262	Diagnosis based on EPOS	In-house domestic pets (cats or dogs, birds) (63 patients with fungal CRS and 144 with non-fungal CRS) cockroaches in house (37 patients with fungal CRS and 40 with non-fungal CRS), carpets (80 fungal CRS, 31 non-fungal CRS), exposure to plants (10 with fungal CRS, 62 with non-fungal CRS), exposure to dust at home or workplace (69 with fungal CRS, 12 with non-fungal CRS), residents in >30-year-old house (26 with fungal CRS, 2 with non-fungal CRS), Resident in overcrowded house floor space per person below ≤26 meter (27 with fungal CRS, 2 with non-fungal CRS), poor exposure to sun (93 with fungal CRS, 47 with non-fungal CRS)
Clarhed et al,¹² 2018	1326	Questionnaire based on EPOS guidelines	Exposure to animals at work, smoking (24%), paper dust, metal dust, animals, moisture/mould/mildew.
Clarhed et al,¹² 2018	1326	Questionnaire based on EPOS guidelines	No more data on percentage for each exposure.
Ahlroth Pind et al,¹³ 2017	415	Diagnosis based on EPOS	Dampness (11.3%), smoking, wood stoves as principal source of heat and exposure to gas, fumes, and dust at work.
Ahlroth Pind et al,¹³ 2017	415	Diagnosis based on EPOS	No more data about percentage for each exposure.
Hwang et al,¹⁴ 2018	1501	Diagnosis based on EPOS	Smoking (712 CRS patients), allergic rhinitis, asthma, and atopic dermatitis, septal deviation, chronic otitis media, rural (368) or urban (1133) residence, blue-collar (1036) white-collar (464) occupation, heavy (475) or light stress (1026) level, presences (305) or absence (1207) suicidal ideation, obesity being overweight (528) or normal and less (973), and alcohol consumption twice a week or more (416) or less than twice a week (1084).
Hwang et al,¹⁴ 2018	1501	Diagnosis based on EPOS	No more data on percentage for each exposure.
Koh et al,¹⁵ 2009	945	A questionnaire based on previously diagnosed CRS	Plant or machine operators and assemblers (881 for men and 57 for women), craft and related trades workers (1387 for men and 282 for women), skilled agricultural or forestry or fishery workers (1045 for men and 1068 for women), sales workers and service workers (1857 for men and 1923 for women), technician and associated professionals (546 for men and 279 for women), professionals (499 men, 279 women), clerical workers (1477 men, 830 women)
Thilsing et al,¹⁶ 2012	243	Diagnosis based on EPOS	Exposure to high-molecular weight agents as (animal dander, fish or shellfish, plant antigen, mites and insects, latex, enzymes, bio aerosols, pharmaceutical products)(6.2%), low-molecular weight agents as (Highly reactive chemicals, isocyanides, reactive cleaning disinfection, wood dust, metal and metal fumes (9.3%), mixed exposure environments as (agricultural, textile production, metal work, irritant peaks) (6%), and low asthma risk agents (environmental tobacco smoke, exhaust, low-risk irritants, or jobs with low levels of exposure to asthmagens), occupational exposure to gasses or fumes or dust or smoke.
Thilsing et al,¹⁶ 2012	243	Diagnosis based on EPOS	No more data on percentage for each exposure
Veloso-Teles et al,¹⁷ 2018	19	Diagnosis based on EPOS	Smoking, alcohol exposure, work sector (spinning 10.5% with nasal polyps, 20.4% with no nasal polyps), wrapping (5.3% with nasal polyps, 7.3% with no nasal polyps), weaving (26.3% with nasal polyps, 15.3% with no nasal polyps), dyeing (10.5% with nasal polyps and 9.2% with no nasal polyps), finishing (21.1% with nasal polyps and 27.6% with no nasal polyps), quality control (5.3% with nasal polyps and 3.6% with no nasal polyps), storing and packing (10.5% with nasal polyps and 7.1% with no nasal polyps), informatics and marketing (0% with nasal polyps and 3.1% with no nasal polyps), administration (0% with nasal polyps, 4.1% with no nasal polyps), designing (5.3% with nasal polyps and 1.5% with no nasal polyps), wood work (5.3% with nasal polyps and 0.5% with no nasal polyps), exposure to domestic fumes (such as: using coal or fire-wood) and domestic animals.
Kajiwara-Morita et al,¹⁸ 2018	2755	A questionnaire based on previously diagnosed CRS	Smoking (32.1% current smokers), alcohol consumption(30.6% who drink alcohol more than 3 times a week, 33.1% who drink alcohol 1-3 times a week), living on a farm (33.6%), exposure to grain dust (33.2%), mine dust (34.5%), wood dust (35.1%), diesel fumes (34.1%), radiation (42.8%)and mold (41.8%). Allergies such as mold allergies (62%), grass allergies (58.7%), and pollen (59.3%).
Putman et al,¹⁹ 2018	2507	Subjective and objective assessment for diagnosis of CRS	prolonged irritant exposure as defined by working at the WTC³ site of 6 months or more (p=1.08 to- 1.34 for 2-5 month exposure compared to p=1.31 to 1.65 for >6 months exposure), exposure to components found in WTC dust, such as metals, and smoking.
Putman et al,¹⁹ 2018	2507	Subjective and objective assessment for diagnosis of CRS	No more data on percentage for each exposure
Clarhed et al,²⁰ 2020	375	Questionnaire based on EPOS guideline	Presence (n=170, 9%) or absence (n=205,4%) of atopy, presence (n=65,10%) or absence (n=310, 5%) of asthma, current (n=103, 7%) or past (n=85, 5%) or never (n=187, 5%) smokers, gas exposure such as cooking fumes, strong acids, dust exposure such as wood, paper, metal dusts, cleaning agents, hair care products, and a cold work environment
Clarhed et al,²⁰ 2020	375	Questionnaire based on EPOS guideline	No more data on percentage for each exposure
Velasquez et al,²¹ 2019	209	Subjective and Objective diagnosis for CRS based on the International Consensus Statement on Allergy and Rhinology	Diesel exposure, exposure to vapors, gases, dusts, fumes, fibers and mists (VGDFFIM) (48.60% CRS patients without nasal polyps, 63.50% CRS patients with nasal polyps)
Brautbar et al,²² 1998	1	Subjective and objective assessment for diagnosis of CRS	Smoking (contain ammonia) and dust exposure (n=1).
Lieu et al,²³ 2000	5848	A questionnaire based on sinusitis symptoms	Current (n= 1523, 30%), former (n= 1466, 30%, never (n=2854, 27.9%) tobacco smoking

CRS: chronic rhinosinusitis, EPOS: European Position Paper on Rhinosinusitis and Nasal Polyps
WTC: world trade center, CRS: chronic rhinosinusitis, EPOS: European Position Paper on Rhinosinusitis and Nasal Polyps