277
10.4 NPs can Pass Through Tropic Levels:
Biotransformation and Biomagnification,
a Serious Concern
NPs can transfer from plants to other trophic levels in a food chain or food web
(Fig. 10.6). CuO NPs can translocate from root to shoot via xylem, while translocation from shoot to root occurred through phloem. In addition to bioaccumulation
and biotransformation, NPs can also be released from roots. The released NPs can
interact with microbes in the rhizospheres and affect their growth (Wang et al.
2012b). An inhibitory effect on the growth of Calotropis gigantea plants has been
documented with exposure to Pb NPs. The leaves of NP-treated plants were reduced
in size and number. Further, feeding of painted grasshoppers on Pb NP-treated plant
leaves has caused their death. Thus, it suggested the bioaccumulation of lead in
plant leaves that induced toxic effects on the plant-dependent grasshoppers
(Padmadhas and Ragunathan 2009). So, NPs have the tendency to transfer from one
trophic level to another in a food chain. Once CeO 2 NPs entered plants, they can
further be transferred to the next trophic level. CeO 2 NPs exposed to kidney bean
plants (P. vulgaris var. red hawk) get transferred to Mexican bean beetles (Epilachna
varivestis) when fed on treated plant leaves. Ce content was further transferred to
spined soldier bugs (Podisus maculiventris) feeding on bean beetles (Majumdar
et al. 2016).
Surface charge of cadmium (Cd)-selenium (Se) QDs affected the level of Cd and
Se accumulation in the leaves of A. thaliana. QDs covered with cationic surfactant
polyethylenimine (PEI) were observed to accumulate more Cd and Se than anionic
Poly(acrylic acid-ethylene glycol) and neutral poly(maleic anhydride-alt- 1octadecene)-poly(ethylene glycol) over QDs. Cd and Se were further transferred to
the next trophic level in Trichoplusia ni caterpillars feeding on QD-treated plant
leaves (Koo et al. 2015).
On TiO 2 NP exposure to Aristolochia debilis plant through roots, NPs were
transferred to leaves. The swallowtail butterfly (Atrophaneura alcinous) larvae
feeding on the leaves not only accumulated TiO 2 NPs but also excreted NPs in the
environment through larval excreta (Kubo-Irie et al. 2016). Likewise, Au NPs were
transferred from Au NP-contaminated leaves to tobacco hornworm (Manduca sexta)
caterpillars. The Au NP bioaccumulation was reported in the gut region of caterpillars feeding on Au NP-contaminated N. tabacum leaves (Judy et al. 2011; Judy et al.
2012). Pests Spodoptera litura F. and Achaea janata L. accumulated Ag NPs from
PVP-coated AgNP-treated castor plant (Ricinus communis L.) leaves. The Ag NPs
were accumulated in the gut and induced oxidative stress. NPs were also released
through feces in the environment (Yasur and Pathipati 2015). La 2 O 3 NPs reduced
plant biomass in lettuce (Lactuca sativa) plants. Further, the crickets, Acheta domesticus, accumulated La 2 O 3 NPs by feeding on treated L. sativa plants. La 2 O 3 NPs
were further transferred to the next trophic level to the mantis (Tenodera aridifolia
sinensis, Sphodromantis centralis) feeding on crickets (Roche et al. 2015). These
adverse effects can travel up to top consumers of the trophic level. In such a study,
10 Phytoresponse to Nanoparticle Exposure
10.4 NPs can Pass Through Tropic Levels:
Biotransformation and Biomagnification,
a Serious Concern
NPs can transfer from plants to other trophic levels in a food chain or food web
(Fig. 10.6). CuO NPs can translocate from root to shoot via xylem, while translocation from shoot to root occurred through phloem. In addition to bioaccumulation
and biotransformation, NPs can also be released from roots. The released NPs can
interact with microbes in the rhizospheres and affect their growth (Wang et al.
2012b). An inhibitory effect on the growth of Calotropis gigantea plants has been
documented with exposure to Pb NPs. The leaves of NP-treated plants were reduced
in size and number. Further, feeding of painted grasshoppers on Pb NP-treated plant
leaves has caused their death. Thus, it suggested the bioaccumulation of lead in
plant leaves that induced toxic effects on the plant-dependent grasshoppers
(Padmadhas and Ragunathan 2009). So, NPs have the tendency to transfer from one
trophic level to another in a food chain. Once CeO 2 NPs entered plants, they can
further be transferred to the next trophic level. CeO 2 NPs exposed to kidney bean
plants (P. vulgaris var. red hawk) get transferred to Mexican bean beetles (Epilachna
varivestis) when fed on treated plant leaves. Ce content was further transferred to
spined soldier bugs (Podisus maculiventris) feeding on bean beetles (Majumdar
et al. 2016).
Surface charge of cadmium (Cd)-selenium (Se) QDs affected the level of Cd and
Se accumulation in the leaves of A. thaliana. QDs covered with cationic surfactant
polyethylenimine (PEI) were observed to accumulate more Cd and Se than anionic
Poly(acrylic acid-ethylene glycol) and neutral poly(maleic anhydride-alt- 1octadecene)-poly(ethylene glycol) over QDs. Cd and Se were further transferred to
the next trophic level in Trichoplusia ni caterpillars feeding on QD-treated plant
leaves (Koo et al. 2015).
On TiO 2 NP exposure to Aristolochia debilis plant through roots, NPs were
transferred to leaves. The swallowtail butterfly (Atrophaneura alcinous) larvae
feeding on the leaves not only accumulated TiO 2 NPs but also excreted NPs in the
environment through larval excreta (Kubo-Irie et al. 2016). Likewise, Au NPs were
transferred from Au NP-contaminated leaves to tobacco hornworm (Manduca sexta)
caterpillars. The Au NP bioaccumulation was reported in the gut region of caterpillars feeding on Au NP-contaminated N. tabacum leaves (Judy et al. 2011; Judy et al.
2012). Pests Spodoptera litura F. and Achaea janata L. accumulated Ag NPs from
PVP-coated AgNP-treated castor plant (Ricinus communis L.) leaves. The Ag NPs
were accumulated in the gut and induced oxidative stress. NPs were also released
through feces in the environment (Yasur and Pathipati 2015). La 2 O 3 NPs reduced
plant biomass in lettuce (Lactuca sativa) plants. Further, the crickets, Acheta domesticus, accumulated La 2 O 3 NPs by feeding on treated L. sativa plants. La 2 O 3 NPs
were further transferred to the next trophic level to the mantis (Tenodera aridifolia
sinensis, Sphodromantis centralis) feeding on crickets (Roche et al. 2015). These
adverse effects can travel up to top consumers of the trophic level. In such a study,
10 Phytoresponse to Nanoparticle Exposure