Pd-nanoparticles cause increased toxicity to kiwifruit pollen compared to soluble Pd(II).
In the present study, endpoints including in vitro pollen performance (i.e., germination and tube growth) and lethality were used as assessments of nanotoxicity. Pollen was treated with 5-10 nm-sized Pd particles, similar to those released into the environment by catalytic car exhaust converters. Results showed Pd-nanoparticles altered kiwifruit pollen morphology and entered the grains more rapidly and to a greater extent than soluble Pd(II). At particulate Pd concentrations well below those of soluble Pd(II), pollen grains experienced rapid losses in endogenous calcium and pollen plasma membrane damage was induced. This resulted in severe inhibition and subsequent cessation of pollen tube emergence and elongation at particulate Pd concentrations as low as 0.4 mg L(-1). Particulate Pd emissions related to automobile traffic have been increasing and are accumulating in the environment. This could seriously jeopardize in vivo pollen function, with impacts at an ecosystem level.
Speranza
Anna
A
Dipartimento di Biologia, Università di Bologna, via Irnerio 42, 40126 Bologna, Italy. anna.speranza@unibo.it
Leopold
Kerstin
K
Maier
Marina
M
Taddei
Anna Rita
AR
Scoccianti
Valeria
V
D029042:Actinidia / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D004784:Environmental Monitoring; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D010165:Palladium / Q000737:chemistry / Q000633:toxicity*; D011058:Pollen / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D012995:Solubility
D010165:Palladium; D002118:Calcium