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Explora: Environment
and Resource Environmental contamination of titanium

solid particles suspended in water. 120 TiO can originate Simonin et al. added 1 – 500 mg/kg nano scale TiO to
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from the natural weathering of Ti minerals or industrial the soil for 90 days and observed significant shifts in several
processes, such as the production of TiO pigments. In bacterial groups, leading to compromised nitrification
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some cases, Ti can form complexes with organic matter in and other nitrogen cycling processes. Meanwhile, Moll
water, resulting incolloidal complexes that may enhance et al. showed that although prokaryotic organisms
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its mobility. Sediments and suspended matter particles were impacted by TiO exposure in the soil, fungal
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can transport Ti within aquatic systems, affecting its groups remained unaffected. Bellani et al. reported
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distribution and sedimentation processes. 121 Although dose-dependent impacts of nanoscale TiO on bacterial
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TiO NPs are known to aggregate rapidly upon contact diversity and observed that 800 mg/kg induced changes,
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with solutions lacking electrolytes, it should be noted but 80 mg/kg had little impact on bacterial diversity and
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that this process is influenced by a variety of factors. For populations. Conversely, Kaur et al. exposed soils to 1 –
example, TiO NPs tend to assemble in seawater within 20 mg/L TiO and reported dose-dependent impacts, with
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an hour, whereas they are stable in treated wastewater for stimulated microfloral growth and activity at low doses
hours. 97,122 Furthermore, Gan et al. reported that natural but inhibitory effects at high concentrations (>15 mg/L).
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organic matter inhibited the aggregation of TiO NPs. Interestingly, contradictory results were obtained by
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Notably, when using coagulation techniques to extract Zhang et al., who exposed soils to 1,000 mg/kg TiO and
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TiO NPs from water, coagulant types and water quality Fe O NPs. The authors observed changes in soil pH and
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can significantly impact overall efficacy. Alkalinity, natural available nutrient fractions, but there was no impact on the
organic matter contents, and the type of ionic solutes and populations of soil bacteria or fungi.
their strength are the factors that usually influence water The existing literature on plant–Ti interactions falls into
quality parameters. Several groups have documented three general categories, includingphytotoxicity, growth
the application of Ti salts as an excellent coagulant for promotion/disease suppression, and the biosynthesis of
the purification of natural water and wastewater. 122-124 nanoscale TiO for other purposes (Tables 4, S3 and S4). The
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TiO₂ NPs’ remarkable adsorption and photo catalytic number of papers published in the former two categories
degradation properties make them effective for treating is roughly equivalent, with the vast majority being focused
environmental pollutants. A suite of contaminants in soil, on nanoscale TiO ; the literature on biosynthesis is more
water, and air could be degraded by TiO₂ NPs due to their limited (Figure 2). 2
potent oxidative potential. In aquatic environments,
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the adsorption or redox transformation of pollutants With regard to phytotoxicity, a number of mechanisms
by TiO₂ NPs maydecrease the elements’ mobility and have been proposedfor TiO -induced toxicity
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bioavailability. (Figures 3 and S2). Doronila and Fox reported on the
regrowth of native plant species on a TiO residue pond
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Improper disposal of waste materials that contain Ti in Australia, and observed that by 5 years, species richness
can result in leachingto soil and groundwater. This occurs and metal contents were largely equivalent to the control
when industrial wastes, construction debris, or discarded sites. Experimentally, Asliand Neumann exposed corn
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consumer products with Ti are not managed and disposed to TiO colloidal suspensions under laboratory hydroponic
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of properly. Some agricultural practices involve the use of or soil conditions. They noted a reduction in planta water
Ti-based materials, such as TiO , as a whitening agent in flow, potentially resulting from apoplastic inhibition;
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animal feed. Runoff from agricultural fields carries these however, shoot production recovered after extended
materials into nearby water bodies or soil. Additionally, exposure. Besides, Ghosh et al. observed increased lipid
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stormwater runoff from urban areas may also transport peroxidation and DNA damage in TiO (4 mM)-exposed
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these particles into water bodies. Notably, accidental spills onion and tobacco. Similarly, Song et al. observed a
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of Ti-containing materials can result in the sudden release dose-dependent toxicity in Lemna minor L. upon anatase
of Ti into the environment, including soil and water. 125 TiO NP exposure, with concentrations above 200 mg/L
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causing progressively greater impact.
4.3. Bioavailability and toxicity of Ti
Alternatively, Larue et al. reported minimal
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4.3.1. Microorganism and plant-Ti interactions physiological impact on wheat and canola from TiO
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The toxicity of NPsto plants and microorganismsdepends NP exposure, despite Ti accumulation occurring in both
not only on their concentration but also on the particle species. Song et al. demonstrated minimal phytotoxicity
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size. A number of published papers investigated the impact of nanoscale TiO to three plant species as measured by a
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of Ti on soil microorganisms and reported that TiO can range of parameters; the authors suggested that particle
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inhibit the growth of essential soil microorganisms. 126,127 agglomeration under environmentally relevant conditions
Volume 2 Issue 3 (2025) 12 doi: 10.36922/EER025130027