Corrigendum to “Effects of radiofrequency electromagnetic field (RF-EMF) exposure on male fertility: A systematic review of experimental studies on non-human mammals and human sperm in vitro” [Environ. Int. 185 (2024) 108509]

The authors of the article with the title “Effects of radiofrequency electromagnetic field (RF-EMF) exposure on male fertility: A systematic review of experimental studies on non-human mammals and human sperm in vitro” regret to report a few inconsistencies detected in the article after its publication, due to errors that inadvertently occurred in the extraction of the original data and in the misfiling of one study for its RoB assessment before the elaboration of the forest plots. One error involved the way in which we extracted the data on the endpoint “Nonpregnant females over paired females” of Saunders et al. (1983) and Goud et al. (1982), and the data on the endpoint “Litter size” of Goud et al. (1982). In particular, in the Saunders study on the rate of nonpregnant females, a group of 24 exposed male mice, matched with a group of 18 sham exposed mice, were mated at different times after exposure, for a total of 10 matings, to groups of unexposed females. In the Goud studies on the rate of nonpregnant females and on the litter size, a group of 25 exposed male mice, matched with a group of 25 sham exposed mice, were mated at different times after exposure, for a total of 3 matings, to groups of unexposed females. We erroneously considered each mating as an independent experiment, thus not applying a weighting correction for using a single group of exposed animals for multiple matings. This resulted in an excessive weighting given to the results from the Saunders and Goud studies. The error has been corrected by aggregating all pregnancy events from all mating rounds as a single result, even though this approach may have blurred a possible differential germ cell stage sensitivity. Another error consisted in misfiling the study of Ma et al. (2014) as “low or some concern” instead of as “high concern” (as correctly reported in all supplementary files relative to RoB) before the elaboration of the “Nonpregnant females over paired females” and “Litter size” forest plots. The errors have been corrected by attributing the correct RoB classification to the study. The correction of these errors resulted in the following changes: Rate of “nonpregnant females over paired females” The number of studies rated as “low or some concern” changed from 19 to 9 and the pooled OR decreased from 2.39 (95% CI 1.52 to 3.74) to 1.68 (95% CI 1.06 to 2.65). The measure of heterogeneity I² decreased from 59.99% to 20.59%. The grade of certainty attributed to the pooled effect size according to the GRADE criteria changed from “moderate” to “high” since it was no longer downgraded by one level for “inconsistency”. Litter size The number of studies rated as “low or some concern” changed from 16 to 15 without any change in the pooled SMD value. The corrections resulted in changes to part of the text and some of the tables, figures and supplementary files. Text changes – In the abstract, the text “The assessment of certainty according to the GRADE methodology assigned a moderate certainty to the reduction of pregnancy rate and…” is replaced by “The assessment of certainty according to the GRADE methodology assigned a high certainty to the reduction of pregnancy rate (an effect largely driven by a single study carried out at an extremely high SAR) and…”– In the abstract, the text “Nevertheless, the associations between RF-EMF exposure and decrease of pregnancy rate and sperm count, to which moderate and low certainty were attributed,…” is replaced by “Nevertheless, the associations between RF-EMF exposure and decrease of pregnancy rate and sperm count, to which high and low certainty were attributed,…”– Within the paragraph “3.5.2.1. Decrease of fertility”, the text of the section “Number of nonpregnant females over paired females” is changed as follows: “Nine studies, rated at “low or some concern” RoB level, evaluated male fertility by the number of nonpregnant females over the number of paired females. The pooled OR value of these studies was 1.68 (95 % CI 1.06 to 2.65), suggesting an RF-EMF exposure-associated decrease of male fertility (revised Fig. 5). The average SAR tested in these studies was 6.98 W/kg (SD 13.78, 0.31–43.4 min–max). Two further studies rated at “high concern” RoB level yielded an OR value of 2.81 (95 % CI 1.44 to 5.47). In the section “Number of nonpregnant females over paired females: Subgroup analysis”, the text “although only the latter yielded a statistically significant pooled OR value.” is deleted.– Within the same paragraph 3.5.2.1., the text of the section “Litter size” is changed as follows: “The pooled SMD of 0.04 (95 % CI −0.15 to 0.23) for the 15 studies at “low or some concern” RoB level showed that there was not a statistically significant decrease of litter size after RF-EMF exposure. The average SAR tested in these studies was 25.83 W/kg (SD 48.08, 0.31–141.4 min–max). Three further studies rated at “high concern” RoB level yielded a SMD value of −0.83 (95 % CI −4.21 to 2.55) (revised Fig. 6).”– Within the paragraph “3.8. Certainty assessment”, the text of the section “Effects on fertility” is changed as follows: “The OR for infertile males, spanning from 0.32 to 5.94, is consistent with null. We downrated the certainty to very low, for RoB by one level, all studies being at “some concern”, and for imprecision by 2 levels, due to the width of the 95 % CI of the pooled effect size crossing the null hypothesis, and the limited number of studies. The SMD for litter size is similarly consistent with no effect, spanning from − 0.15 to 0.23. We downrated the certainty to moderate, for RoB by one level, all but one study being at “some concern”. In spite of a significant Egger's test, we did not downgrade for publication bias because the pooled effect size was consistent with null. The result was not upgraded for consistency across species because the between-group difference was borderline significant. The OR for nonpregnant females, spanning from 1.06 to 2.65, is consistent with a detrimental effect of exposure. We downrated the certainty for RoB by one level, all but one study being at “some concern”. We upgraded the certainty to high for consistency among species. We point out that the exclusion of the Saunders 1983 study that tested a SAR of 43.4 W/kg, i.e. an exposure level about 100 times higher than the current exposure limits for general population, would decrease the pooled OR from 1.68 to 1.32 with confidence interval crossing the null hypothesis. Therefore, a detrimental effect on the pregnancy rate at exposure levels relevant for human populations remains questionable.– In the discussion, paragraph 4.1. Summary of the evidence and interpretation of the results, the text “From experimental animal studies there is moderate certainty of evidence that RF-EMF exposure reduces rate of pregnancy…” is replaced by “From experimental animal studies there is high certainty of evidence that RF-EMF exposure reduces rate of pregnancy…”. In addition, the sentence “The result on the decrease of pregnancy rate is consistent with this hypothesis, as shown by the observation that the pooled effect size is statistically significant only in the subgroup of studies exposed to SAR equal to or higher than 5 W/kg and the statistically significant slope of the linear dose-response relationship.” is replaced by “The statistically significant slope of the linear dose-response relationship for the decrease of pregnancy rate would support this hypothesis.“– In the paragraph “4.4. Implications for policy and research”, the sentence “In conclusion, our systematic review and meta-analyses indicate a possible detrimental effect of RF-EMF exposure on pregnancy rate…” is replaced by “In conclusion, our systematic review and meta-analyses indicate a detrimental effect of RF-EMF exposure on pregnancy rate…”. In addition, in the sentence “75–80 % tested exposure levels above 0.4 W/kg (ICNIRP basic restriction for workers) and 46–53 % tested exposure levels above 4 W/kg (ICNIRP health effect level) (ICNIRP, 2020).”, “46–53 %” is replaced by “32–53 %”.Changes to tables, figures and supplementary files The corrected tables (revised Tables 3 and 5) are shown below, where changes are highlighted in bold. The corrected figures (revised Figs. 5 and 6) are similarly reported in this corrigendum, whereas the corrected supplementary files (revised Supplementary Files 4a, 5, 6 and 8) are included as supplementary materials. Wherever in the paper the Tables 3 and 5, Figs. 5 and 6 or Supplementary Files 4a, 5, 6, and 8 are mentioned, it is intended that they are replaced by the revised versions included in this corrigendum. The authors would like to apologise for any inconvenience caused.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.