Table 2 Neurodevelopmental outcomes of manganese exposure measured in biomarkers from cross-sectional studies
Author, Year | Age (Years) | Country/ Study Name | Number (Girls/Boys) | Sources | Biomarkers | Neurological Assessments | Associations between Manganese in Biomarkers and Neurodevelopmental Outcomes | Adjustment for Covariates | Study Quality |
|---|---|---|---|---|---|---|---|---|---|
Al-Saleh 2019 [40] | 0.2–1 | Saudi Arabia | 206 (96/110) | NA | Maternal blood and urine, infant urine, breast milk | DDST-II, PEDS | NS | Maternal age and BMI, infant’s age, sex, parity, the location of primary health care centers, maternal education and z score weight for age | Medium |
Rink 2014 [41] | 1.1–3.7 | Uruguay | 60 (34/26) | NA | Hair | BSID-III | H-Mn: NS | HOME score, age, child Hb, maternal IQ, SES, Pb, marital status, father education and tester | High |
Bauer 2017 [42] | 10–14 | Italy/PHIME | 142 (79/63) | Fe-Mn alloy plant | Teeth | VRAM | Both low and high prenatal Mn ↓: visuospatial learning and working memory among girls only | Sex, age, SES, videogame use, lead, trial and tooth attrition | High |
Betancourt 2015 [43] | 11 | Ecuador | 93 (46/47) | Water consumption from the river | Hair | PCM | H-Mn: ↓: IQ | Mother’s literacy | Medium |
Bhang 2013 [44] | 8–11 | Korea* | 1001 (474/527) | NA | Blood | WASI, ADS, CBCL | B-Mn: ↓: academic performance, such as thinking, reading, calculation, lower Mn ↓: attention | Age, sex, region, children’s IQ, maternal education and age, levels of cotinine and lead | High |
Bouchard 2007 [45] | 6–15 | Canada | 46 (22/24) | Ground water | Hair | CPRS-R, CTRS-R | H-Mn: ↓: behaviors (teacher-reported hyperactive and oppositional behaviors) | Child’s age, sex and income | High |
Bouchard 2011 [16] | 6–13 | Canada | 362 (194/168) | Ground water | Hair | WASI | H-Mn: ↓: IQ | Maternal education and IQ, income, home stimulation score, family structure, sex and age of child and IQ testing session, source of water and level of iron in tap water | High |
Bouchard 2018 [8] | 6–14 | Canada | 259 (132/127) | Ground water | Hair, saliva, toe nail | WISC-IV | NS, possible beneficial effects in boys | Child’s age, maternal IQ and education, income and IQ tester | High |
Carvalho 2014 [22] | 7–12 | Brazil | 70 (36/34) | Air emissions from Fe-Mn alloy plant | Hair | WISC-III | H-Mn: ↓: estimated IQ, Block Design and Digit Span | Maternal education | High |
Carvalho 2018 [46] | 7–12 | Brazil | 70 (36/34) | Air emissions from Fe-Mn alloy plant | Hair | NEPSY II | H-Mn: ↓: verbal memory, behaviors (hyperactivity), not motor | Age, sex, SES, mother’s education and mother’s IQ | High |
Chan 2015 [47] | 11–13 | USA/NICHD | 266 (128/138) | NA | Teeth | DBD | NS | Child’s race, sex, parental education, marital status and SES | High |
Chiu 2017 [48] | 11–14 | Italy/PHIME | 194 (105/89) | Fe-Mn alloy plant | Teeth | PA, LNMB | Pretnatal T-Mn: ↑: behaviors and motor in boys, T-Mn: ↓: motor (tremor): early postnatal in girls, later postnatal in boys | Children’s age and sex, SES index and tooth attrition | High |
do Nascimento 2015 [49] | 6–12 | Brazil | 69 (34/35) | Drinking water from well water | Hair, blood | RCPM | H-Mn: ↓: cognitive function, B-Mn: NS | Age, sex and parents’ education | High |
Ericson 2007 [50] | 3–9 | USA/SECCYD | 27 (16/11) | NA | Teeth | FTT, CBCL | Prenatal T-Mn: ↓: behaviors (hyperactivity) | Pb, mothers’ education, income and child ethnicity | High |
Frndak 2019 [51] | 6–8 | Uruguay | 345 (155/190) | NA | Hair | CANTAB, W-M | H-Mn: ↑: cognition | Child’s age, sex, Pb, hemoglobin, HOME score, crowding, possessions of wealth and mother’s education | High |
Haynes 2015 [52] | 7–9 | USA/CARES | 404 (187/217) | Air-borne Mn from Fe-Mn refinery | Hair, blood | WISC-IV | Both low and high Mn: ↓: IQ | Parent IQ | Medium |
Haynes 2018 [7] | 7–9 | USA/CARES | 106 (65/41) | Air-borne Mn from Industry | Hair, blood | WISC-IV | H-Mn: ↓: IQ, B-Mn: NS | Parent IQ | Medium |
Hernandez-Bonilla 2011 [53] | 7–11 | Mexico | 172 (84/88) | Air-borne Mn from Mining | Hair, blood | GP, FT, SA | B-Mn: ↓: motor speed and coordination, H-Mn: NS | Pb, Hb, sex, age and maternal education | High |
Hernandez-Bonilla 2016 [54] | 7–11 | Mexico | 267 (136/131) | Air-borne Mn from mining district | Hair | ROCF | H-Mn: ↓: visuoperception and short-term visual memory | Pb, Hb, child’s age and sex, motor dexterity and mother’s IQ | High |
Horton 2018 [55] | 8–11 | Mexico/ELEMENT | 133 (69/64) | Air pollution and diets | Teeth | BASC-2 | Prenatal T-Mn: ↑: behaviors, postnatal T-Mn: ↓: behaviors (internalizing problems) | Maternal education and gestational age | High |
Khan 2011 [56] | 8–11 | Bangladesh | 201 (100/101) | Drinking water from well water | Blood | CBCL | B-Mn: NS | Arsenic, sex, BMI, maternal education and arm circumference | High |
Kicinski 2015 [57] | 13.6–17 | Belgium | 606 (282/324) | Low-level metal exposure from industrial areas | Blood | FT, CPT, DS | B-Mn: NS | Sex, age, smoking, passive smoking, income, occupation, and maternal education | High |
Kim 2009 [58] | 8–11 | Korea | 261 (120/141) | NA | Blood | WISC | B-Mn: ↓: IQ | Age, sex, parental education, income, smoking, birth weight and mother’s age | High |
Lucchini 2012a [59] | 11–14 | Italy | 299 (147/152) | Fe-Mn alloy plant | Hair, blood | WISC | NS | Age, sex, BMI, family size, SES, alcohol consumption, area of residence, Hb, ferritin and parity | High |
Lucchini 2012b [60] | 11–14 | Italy | 311 (153/158) | Fe-Mn alloy plant | Hair, blood, urine | FT, PA, DPD, LNMB | B-Mn and H-Mn: ↓: motor (tremor), urine, air, water, diet: NS, soil Mn: ↓: tremor intensity | Parity, family size, SES, BMI, maternal education, alcohol intake, smoking, Pb and other metals in air, soil and water. | High |
Lucchini 2019 [61] | 6–12 | Italy | 299 (161/138) | Industrial emission, with potential contamination of environment | Hair | WISC, CANTAB | H-Mn: ↓: working memory | Sex, age, maternal IQ and cognitive stimulation besides the confounder distance from the point source | High |
Menezes-Filho 2011 [21] | 6–12 | Brazil | 83 (39/44) | Fe-Mn alloy plant | Hair, blood | WISC-III | H-Mn: ↓: cognition, especially in the verbal domain, B-Mn: NS | Maternal education and nutritional status | Medium |
Menezes-Filho 2014 [62] | 7–12 | Brazil | 70 (36/34) | Air-borne Mn from Fe-Mn alloy plant | Hair | CBCL | H-Mn: ↓: behaviors (externalizing behaviors), more pronounced in girls | Age, sex and maternal IQ | High |
Nascimento 2016 [63] | 6–12 | Brazil | 63 (31/32) | Potential contamination from pesticide | Hair, blood | NEUPSILIN-Inf | B-Mn: ↓: visual attention, visual perception and phonological awareness, H-Mn: ↓: working memory | IQ, age, sex and parents’ education | High |
Oulhote 2014 [15] | 6–13 | Canada | 375 (200/175) | Drinking water from ground water | Hair | WASI, CPT-II, FT, SA | H-Mn: ↓: memory, attention, not hyperactivity, motor: a nonlinear association, ↑: 0.3–0.8 μg/g, ↓: >  10 μg/g, but there were very few observations with such high levels | Child’s sex, age, maternal education and IQ, income, maternal depressive symptoms and tap water lead concentrations. | High |
Parvez 2011 [64] | 8–11 | Bangladesh | 304 (153/151) | Drinking water from well water | Blood | BOT-2 | B-Mn: NS | Sex, school attendance, head circumference, mother’s intelligence, ferritin, selenium and Pb | High |
Riojas-RodrÃguez 2010 [6] | 7–11 | Mexico | 172 (99/73) | Air-borne Mn from mining district | Hair, blood | WISC | H-Mn: ↓: IQ, B-Mn: NS | Pb, age, sex, nutritional status, maternal education and IQ | High |
Rugless 2014 [65] | 7–9 | USA/CARES | 55 (35/20) | Air emissions from Fe-Mn refinery | Hair, blood | APS | H-Mn and B-Mn: ↓: postural balance | Sex, height/weight ratio, parent IQ, education, Pb and age | Medium |
Torrente 2005 [66] | 12–14 | Spain | 100 (61/39) | Industrial emission | Hair | AMP | H-Mn: NS | SES and age | Low |
Torres-Agustin 2013 [67] | 7–11 | Mexico | 174 (86/88) | Air-borne Mn from mining district | Hair, blood | CAVLT | H-Mn: ↓: long-term memory and learning, B-Mn: NS | Child’s sex, Pb, age, Hb and maternal education | High |
Wasserman 2006 [9] | 10 | Bangladesh | 142 (72/70) | Drinking water from well water | Blood | WISC-III | B-Mn: NS | Maternal education and IQ, house type, family ownership of a television, child height and head circumference | High |
Wright 2006 [68] | 11–13 | USA | 31 (16/15) | Mining waste | Hair | WASI | H-Mn: ↓: Full Scale IQ, Verbal IQ | Sex and maternal education | Low |