Commentary Response to: Bouwman, H. et al. hallogenated pollutants in terrestrial and aquatic bird eggs: Converging patterns of pollutant profiles, and impacts and risks from higher levels Environ. Res. (2013) http://dx.doi.org/10.1016/j.envres.2013.06.003 Donald R. Roberts a,n , Rajendra Maharaj b , Maureen Coetzee c , Richard H. Hunt c , John Govere d , Richard Tren e , Jasson Urbach f , Amir Attaran g , Lucille Blumberg h a Uniformed Services University of the Health Sciences, Bethesda, MD, USA b Malaria Research Unit, South African Medical Research Council, Durban, South Africa c Wits Research Institute for Malaria, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa d Malaria Vector Control Specialist, Nelspruit, Mpumalanga, South Africa e Africa Fighting Malaria, Washington, DC, USA f Africa Fighting Malaria, Durban, South Africa g University of Ottawa, Faculty of Law and Medicine, Ottawa, Ontario, Canada h National Institute for Communicable Diseases, National Health Laboratory Service, Johannesburg, South Africa article info Article history: Received 13 November 2013 Received in revised form 22 January 2014 Accepted 24 January 2014 Keywords: DDT DDE Bird egg shells Cattle Egrets Malaria South Africa abstract Bouwman and coauthors present data and analyses of DDT and other halogenated pollutants in environmental samples and based on their data and analyses thereof, argue against the use of DDT for malaria control. Regrettably, the analyses, presentations, and interpretations of data presented by Bouwman and coauthors are biased and erroneous. & 2014 Elsevier Inc. All rights reserved. 1. Introduction The authors report a study of chemical levels in bird eggs for an area where DDT is sprayed inside houses for malaria control, and report on DDT levels in bird eggs for sample sites in both sprayed and unsprayed areas. The weight of scientific merit of their study rests heavily on reporting: (1) fewer piscivore bird populations in the region than they expected; (2) data for higher levels of DDT in sprayed versus unsprayed areas; (3) greater shell thinning in eggs of Cattle Egrets in sprayed areas; and (4) regression analysis showing shells of Cattle Egret eggs were thinner when they contained higher concentrations of DDE. We deal with each of these points below. (1) The authors' suggestion that fewer piscivore bird populations are present than they expected, is not supported by data to show that this is actually the case or that DDT is causally linked to the absence of birds in the region. Nor do they provide references to past occurrences of birds in the study area. (2) In the present study, Bouwman and co-authors use data on eggs of House Sparrows to show high DDT concentrations in bird populations of the DDT-sprayed area. Since the DDT-laden sparrows were unharmed and reproducing successfully, the authors speculate that perhaps the sparrows had developed DDT tolerance. Their speculation is unwarranted because they have no evidence that sparrows have ever been harmed by DDT exposures. The weight of evidence suggests that the House Sparrow, like the American Robin (see Harris et al., 2000. Arch. Environ. Contam. Toxicol. 39(2), 205–220; Gill et al., 2003. Ecotoxicology 12(1–4), 113–123), is not reproductively impaired by environmental accumulations of DDT residues. Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/envres Environmental Research http://dx.doi.org/10.1016/j.envres.2014.01.010 0013-9351/& 2014 Elsevier Inc. All rights reserved. DOI of original article: http://dx.doi.org/10.1016/j.envres.2013.06.003 n Corresponding author. E-mail address: drdonaldroberts42@gmail.com (D.R. Roberts). Please cite this article as: Roberts, D.R., et al., Response to: Bouwman, H. et al. hallogenated pollutants in terrestrial and aquatic bird eggs:.... Environ. Res. (2014), http://dx.doi.org/10.1016/j.envres.2014.01.010i Environmental Research ∎ (∎∎∎∎) ∎∎∎–∎∎∎