• Risks of granules and treated seeds to birds on arable fields

      de Leeuw J; Gorree M; de Snoo GR; Tamis WLM; van der Poll RJ; Luttik R; ACT; Centrum voor Milieukunde CML Rijksuniversiteit Leiden (Rijksinstituut voor Volksgezondheid en Milieu RIVM, 1995-06-30)
      Before a pesticide is approved for use on the Dutch market, an assessment must be made of the risk of its use to non-target organisms. This study considers the extent to which use of pesticides, in the form of granules or seed-treatment agents, constitutes a potential risk to birds. If treated seeds or granules remain on the field surface after drilling, they may be picked up by birds for two reasons: seeds may be taken for food, or granules and pelleted seeds may be taken for potential grit (small stones used by birds to grind their food). There are presently a number of gaps in the knowledge required to assess the risk of using such granules and seed-treatment agents. First of all, nothing is known about the grit consumption of farmland birds in the Netherlands. In addition, it is unknown what proportion of seeds remains on the surface after drilling. This study describes the grit particles consumed by farmland birds, it establishes their resemblance to granules and pelleted seeds, and an assessment of the potential risk is presented. In addition estimates of the number of seeds remaining available to birds at the soil surface after drilling various crops are given ; an analysis of the factors that can influence the numbers remaining at the soil surface is carried out ; and the incorporation of these results in the risk assessment procedure are discussed.<br>