Toxicokinetics
Search terms	TOPIC (TITLE/ABSTRACT in PubMed): nickel* OR Ni AND TOPIC (All fields in PubMed): (absor* OR tissue* OR metaboli* OR excret* OR kinetic* OR toxicokinetic* OR pharmacokinetic* OR degrad* OR biotrans* OR eliminat* OR PBPK OR PBTK OR PBK) AND TOPIC (All fields in PubMed): (rat OR rats OR mouse OR mice OR rabbit* OR guinea OR hamster* OR primate* OR monkey* OR pig* OR minipig* OR dog* OR cat OR cats OR mink*)
Toxicity in experimental animals
Search terms	TOPIC (TITLE/ABSTRACT in PubMed): nickel* OR Ni AND TOPIC (ALL FIELDS in PubMed): (acute OR chronic OR tox* OR cancer* OR carcino* OR tumor* OR tumour* OR organ* OR immun* OR neuro* OR developmental OR teratogen* OR repro* OR liver OR hepato* OR kidney* OR brain* OR lung OR lungs OR heart* OR thyroid* OR spermat* OR testes OR ovar* OR uterus)
	AND TOPIC (ALL FIELDS in PubMed): (rat OR rats OR mouse OR mice OR rabbit* OR guinea OR hamster* OR primate* OR monkey* OR pig* OR minipig* OR dog* OR cat OR cats OR mink*)
In vitro and in vivo genotoxicity and mode of action
Search terms	TOPIC (TITLE/ABSTRACT in PubMed): nickel* OR Ni AND TOPIC (ALL FIELDS in PubMed): (“in vitro” OR “mode of action” OR endocrin* OR estrogen* OR oestrogen* OR androgen* OR “mechanism of action” OR apoptosis OR “oxidative stress” OR cytotox* OR genotox* OR mutagen* OR clastogen* OR aneugen* OR chromosom* OR chromatid)
Human observations (epi or biomo)
Search terms	TOPIC (TITLE/ABSTRACT in WoS): nickel* OR Ni AND TOPIC (ALL FIELDS in PubMed): oral AND TOPIC (ALL FIELDS in PubMed): (epidemio* OR intervention OR exposure* OR “case study*” OR “case control*” OR “case report*” OR poison* OR cohort* OR cross‐sectional OR occupational OR “adverse effect*” OR “occupational case*” OR “biological marker” OR human health OR meta‐analys*)