Table 5.
Vaccine, olfactory, reproductive, and other health effects from exposure to electronic waste
| Exposure setting | Exposure setting | Control population | Toxic chemicals | Health outcomes | |
|---|---|---|---|---|---|
| Vaccine | |||||
| Lin et al (2017)49 | Cross-sectional: exposed town vs reference town, China | 157 preschool children aged 3–7 years | 127 preschool children aged 3–7 years | Lead, zinc, arsenic, mercury, cadmium, chromium, copper, manganese, and selenium | Blood lead=9·43 μg/dL vs 6·79 μg/dL (p<0·001), elevated essential elements (manganese, copper, zinc, chromium; p<0·05) in exposed group. Lower antibody titres of diphtheria, pertussis, tetanus, Japanese encephalitis, polio, measles (all p<0·05), hepatitis B (p>0·05). Significant association between antibody titres and elevated lead (OR=0·31–0·45), copper (OR=0·47–0·60), and zinc (OR=0·48–0·56; all p<0·05). |
| Lin et al (2016)50 | Cross-sectional: exposed town vs reference town, China | 263 preschool children aged 2–7 years | 115 preschool children aged 2–7 years | Lead | Blood lead=5·61 μg/dL vs 3·57 μg/dL (p<0·001). Lower antibody titres (median measles Ab=669 mIU/mL vs 1047 mIU/mL, mumps Ab=272 U/mL vs 492 U/mL, rubella Ab=37·08 IU/mL vs 66·50 IU/mL; all p<0·001). Anti-measles Ab titre positively associated with anti-mumps and rubella (r=0·16 and 0·37; p<0·01), Positive correlation between anti-mumps and anti-rubella Ab titres (r=0·17; p<0·01). No correlation between blood lead and anti-MMR Ab titres (p>0·05). |
| Xu et al (2015)51 | Cross-sectional: exposed town vs reference town, China | 301 kindergarten children (mean age 4·77 years) | 289 kindergarten children (mean age 4·47 years) | Lead | Blood lead=6·76 μg/dL vs 6·05 μg/dL (p<0·01; 2011=8·76 μg/dL vs 7·89 μg/dL, 2012=5·83 μg/dL vs 4·61 μg/dL; both p<0·001), median HBsAb titres=1·04 s/co vs 4·06 s/co; p<0·001; 2011=0·83 s/co vs 4·64 s/co, 2012=1·31 s/co vs 3·80 s/co; p<0·001). HBsAb titres negatively associated with blood lead (β=−0·45 in 2011 and β=−0·37 in 2012; p<0·001). |
| Auditory and olfactory | |||||
| Liu et al (2018)52 | Cross-sectional: exposed town vs reference town, China | 146 preschool children aged 3–7 years | 88 preschool children aged 3–7 years | Lead and cadmium | Blood lead=4·94 μg/dL vs 3·85 μg/dL (p<0·001), urinary cadmium=2·49 μg/g cre vs 1·80 μg/g cre (p>0·05). Hearing loss=28·8% vs 13·6% (p<0·001). Hearing loss for lead exposure: AOR=1·24 (95% CI 1·03 to 1·49). |
| Xu et al (2020)37 | Cross-sectional: exposed town vs reference town, China | 68 preschool children aged 3–7 years | 48 preschool children aged 3–7 years | Lead and cadmium | Blood lead=5·29 vs 3·63 μg/dL; p<0·001, urinary cadmium=1·52 vs 1·21 μg/g cre; p>0·05, hearing loss (>25 dB)=50·0% vs 20·8%. AOR of lead for hearing loss=1·40 (95% CI 1·06 to 1·84). |
| Zhang et al (2017)53 | Cross sectional: exposed town vs reference town, China | 61 preschool children aged 4–7 years | 57 preschool children aged 4–7 years | Lead | Blood lead=9·40 mg/dL vs 5·04 mg/dL, serum BDNF=35·91 ng/mL vs 28·10 ng/mL (both p<0·001), IGF-1=170 vs 154 ng/mL (p>0·05), BDNF positively correlated with blood lead (β=0·68; p<0·01). Lower item and source olfactory memory scores (at 15 min, 5 h, and 24 h) among exposed (p<0·01), and negatively correlated with blood lead (β=−0·29 to −0·16; p<0·05), BDNF (−0·23 to −0·19; p<0·05). |
| Reproductive | |||||
| Yu et al (2018)76 | Exploratory: exposed town vs hospital bank, China | 32 local adult men (mean age 38·7 years) | 25 local adult men (mean age 36·0 years) | PBDE | BDE-28=5·02 pg/g vs 1·62 pg/g, BDE-47=6·75 pg/g vs 1·32 pg/g, BDE-153=7·36 pg/g vs 3·62 pg/g, (p<0·05) in semen, lower sperm count, sperm progressive motility among exposed, tail DNA (comet assay)=57·88% vs 33·55%, apoptosis rate (TUNEL assay)=32% vs 20% (all p<0·05). Inverse correlation between sperm concentration and count with BDE-47 (β=−0·29 and −0·40; p<0·05), sperm progressive motility ([A+B]%) and sperm viability negatively correlated with BDE-100 in dust (β=−0·36 and −0·11; p<0·05), positive correlation between BDE-28, BDE-47, BDE-153 and paired semen samples (rs=0·36–0·54; p<0·05). |
| Wang et al (2018)54 | Cross-sectional: exposed town vs reference town, China | 146 local male residents (mean age 35·8 years) | 121 local male residents (mean age 34·9 years) | Lead, copper, zinc, iron, calcium, magnesium, selenium, and PCBs | Higher blood lead, PCBs, MDA, and lower calcium, magnesium, SOD, GSH among exposed (p<0·05, data not shown), MDA, lead, calcium, magnesium and DNA damage associated with the duration of exposure (p<0·05, data not shown). DNA damage in lymphocytes and spermatozoa (TDNA%, TM, OTM by comet assay), DNA aberrations (CA=8·01 vs 1·80% and CBMN=26·30% vs 4·52%) greater in exposed (all p<0·01). Semen volume=1·39 mL vs 2·52 mL, motility rate=45·01% vs 58·48% and reduced sperm count among exposed (p<0·05). Exposure duration, PCBs, MDA, and lead revealed risk factors of semen quality (all p<0·05). 13 genes expression of mRNA upregulated and 7 genes downregulated. |
| Hepatic | |||||
| Chen et al (2019)46 | Cross-sectional: exposed vs reference groups, China | 158 hospitalised patients aged 4–85 years | 109 hospitalised patients aged 4–85 years | Lead and cadmium | Blood lead=8·7 μg/dL vs 5·1 μg/dL (p<0·001), cadmium=2·1 μg/L vs 2·6 μg/L (p>0·05), GGT=68·0 vs 26·0 (p<0·001), no difference of AST, ALT, AST/ALT, LDH among groups (p>0·05). Blood lead positively correlated with cadmium (0·117; p<0·05). Positive correlation between blood lead and ALT (r=0·111; p<0·05), Blood cadmium correlated with AST (r=0·22) and ALT (0·21; both p<0·001). Elevated blood lead (≥5 μg/dL) inducing abnormal liver function (AOR=1·94, 95% CI 1·00 to 3·73). |
| Renal | |||||
| Xu et al (2015)70 | Cross-sectional: exposed town vs control town, China | 40 local residents aged 15–65 years | 15 local residents aged 15–65 years | PCB and PBDE | ∑PCBs=964 ng/g vs 68 ng/g (p<0·001), ∑PBDEs 139 ng/g vs 75 ng/g (p>0·05). Serum creatinine=87·05 μmol/L vs 74·49 μmol/L, β2-MG=0·25 mg/L vs 0·18 mg/L (both p<0·001). ∑PCBs positively correlated with serum creatinine (r=0·40) and β2-MG (r=0·70; both p<0·01). |
| Oral | |||||
| Hou et al (2020)55 | Cross-sectional: exposed town vs control town, China | 357 preschool children aged 2·5–6 years | 217 preschool children aged 2·5–6 years | Lead | Blood lead=4·86 μg/dL vs 3·47 μg/dL, IL-6=6·96 pg/mL vs 2·76 pg/mL, and TNF-α=6·51 pg/mL vs 1·29 pg/mL (all p<0·05). Lower salivary sialic acids=9·58 mg/dL vs 17·57 mg/dL (p<0·05), dental caries=62·5% vs 53·9% (p<0·05). Negative association between blood lead and salivary sialic acid (B=−5·59, 95% CI −9·62 to −1·55), in mediation analysis, inverse correlation between blood lead and salivary sialic acid through IL-6 (B=−0·95, 95% CI −1·70 to −0·20). |
| Metabolic | |||||
| Song et al (2019)83 | Cross-sectional: exposed villages vs reference village, China | 119 elderly residents aged 56–93 years | 16 elderly residents aged 56–93 years | BPA and 6 alternatives | Serum BPA=3·2 ng/mL vs 2·8 ng/mL (p<0·05), dominant BPA alternatives=BPF (71%), BPAP (13%), BPAF (8%), BPS (7%). Abnormal FBG (<3·9 mmol/L or >6·1 mmol/L)=45% vs 31% (p<0·05), and associated with BPA (data not shown; p<0·05), high BPAF negatively correlated with low FBG (r=−0·30; p<0·001). |
OR=odds ratio. Ab=antibody. MMR=measles, mumps, and rubella. HBsAb=hepatitis B surface antibody. cre=creatinine. AOR=adjusted OR. BDNF=brain derived neurotrophic factor. IGF-1=insulin-like growth factor. PBDE=polybrominated diphenyl ether. BDE=brominated diphenyl ether. TUNEL=TdT-mediated dUTP Nick-End Labelling. PCB=polychlorinated bisphenol. MDA=malondialdehyde. SOD=superoxide dismutase. GSH=glutathione. TDNA=DNA in the comet tail. CA=chromosome aberrations. TM=tail moment. OTM=olive tail moment. CBMN=cytokinesis-block micronucleus. GGT=gamma glutamyl transpeptidase. AST=aspartate aminotransferase. ALT=alanine aminotransferase. β2-MG=β2-microglobulin. BPAP=bisphenol AP. BPAF=bisphenol AF. BPS=bisphenol S. FBG=fasting blood glucose.