Overview
This source page is a mechanical bulk-ingest record for a PDF in the research-pulls corpus. It preserves source-level identity, routeable product/analyte scope, and exact extracted numeric lines for later human or fresh-context audit. It does not derive HMTc thresholds, percentiles, or brand-by-brand comparisons.
Key numbers
The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:
- limited number of research-scale field occurrence studies4,6, there (organic and inorganic) over a broad range of sizes, including at
- water9–11. Surface waters (rivers, lakes) generally provide over 80% remove over 90% of ENPs from sewage through chemical, biologi-
- Review therefore focuses on the potential for ENPs to occur and be colloidal-sized materials; 30% of the natural organic matter is below
- the range of 1–20 nm, leading to a drop-off in measured particle
- organic carbon, 50–100% of the iron, and 30–70% of the aluminium only a few TiO2 particles upon extraction from river water and
- ical, two-dimensional and elongated rod13,35), which means that ates to humics and other particles in surface waters63. Limited field
- unit processes concluded that conventional DWTPs remove >80% ENP concentrations. Natural and engineered systems seem to be
- removal rates of 97%, 99% and 99.99% of NPs, depending on unit 0.04 μg l–1, 147 μg l–1 and 0.28 μg l–1 for Ag, TiO2 and ZnO, respec-
- sub-μg l–1 range5. More realistic scenario estimates were tens of for bank filtration of the same ENPs were 3.3 μg l–1, 13 μg l–1 and
- no pulses and contains only 3.1 ng l–1 particulate Ti with a median organic material (that is, >10,000 Daltons, which equates to roughly
- equivalent spherical diameter of 124 nm, indicating >99% removal of >3 nm spherical NP86), which some attribute to rod-shaped or
- water. The same study indicated >99% removal across the DWTP of ing)88,89. The operational definition originated before 1970, when
- Ce-based particles, which had mean equivalent spherical diameters of 0.2–0.45 μm filters were recognized to slow or prevent the biologi-
- by the USEPA, nanomaterials were nominated for inclusion in rials contains 1–2 wt% TiO2, which is added for colour, strength and
- DWTP monitoring. However, due to the general lack of evidence UV protection97, and is used in potable water systems and premise
- monly used in ENPs, but these metals tend to occur at <50 ppt sized elements in tap waters. In this study, tap waters (n =44, where
- Thus, even without relying on 80% to >99% removal of NPs within collected from three buildings, and particles containing Pb, Sn, Fe
- mum of 0.4%, 18%, 16% and 0.2% of the corresponding total dis-
- After purification at centralized DWTPs, tap water travels under frequency. The minimum detectable size104 for the elements was 26,
- silver concentrations in drinking water (reverse-osmosis permeate) per and zinc128. Reported LC50 ranges for mammalian cells are of
- remains debatable135, with some studies showing that TiO2 NPs drinking water community to conduct occurrence studies in tap
-
- Chalew, T. E. A., Ajmani, G. S., Huang, H. O. & Schwab, K. J. Evaluating 101. Triantafyllidou, S., Parks, J. & Edwards, M. Lead particles in potable water.
- 531–541 (2018). particle inductively coupled plasma mass spectrometry with the K-means
- contamination scenarios: Case study from a recent coal ash spill. Environ. 111. Ehdaie, B., Krause, C. & Smith, J. A. Porous ceramic tablet embedded
Methods (brief)
- with in-line ICP-MS detection has shown a bi-modal distribution
- potential toxicity of natural or engineered colloids below 500 nm after extraction37,44,54,55. Using spICP-MS56–60, one study was consis-
- water29–31. NNPs are present in essentially all environments at mass higher concentrations (0.2–8.1 μg l–1) in all samples from two Dutch
- concentrations ranging from 1–1,000 mg l–1 in surface waters32. rivers61. Another study used spICP-MS to detect titania concentra-
- plasma mass spectroscopy (SPICP-MS) or use a new time of flight ing water regulations4. However, site-specific mechanistic models
- (SP-TOF-ICP-MS) instrument. These techniques fingerprint NPs show the potential for elevated ENP hot spots in river systems when
- analytically time consuming to collect in field samples and often spiked into surface waters and bench-scale drinking water treatment
- illustrates one study’s spICP-MS data for Ti in river water serving as developing countries, where industrial accidents or un-monitored
- after conventional treatment78. Each spICP-MS ‘pulse’ represents Though DWTPs are not required to monitor for ENPs or NNPs,
- non-ionic metal response by the spICP-MS. The river water (Fig. 2a) they do periodically measure nanoscale materials, either directly or
- the application of spICP-MS for monitoring the mass or number and In some cases, particle counters that detect particles larger than
- lower than current instrument detection limits. No regulations requires only modifications to conventional spICP-MS, demon-
- in tap waters, based on a limited number of field measurements. n is the number of samples analysed from different tap waters) were
- Thus, even without relying on 80% to >99% removal of NPs within collected from three buildings, and particles containing Pb, Sn, Fe
- Fig. 4 | Typical size distribution of metal-containing particles detected in tap waters collected from Phoenix, AZ.
-
- Allaire, M., Wu, H. W. & Lall, U. National trends in drinking water quality methodological approaches for the analysis of complex samples.
- and Wastewater Treatment Infrastructure (American Society of Civil Characterization of a new ICP-TOFMS instrument with continuous and
- tributaries during extreme rainfall and runoff. Appl. Environ. Microb. using inductively-coupled plasma time-of-flight mass spectrometry
Implications
This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.
Wiki pages this source may touch
- Infant Formula Powder
- Shellfish (shrimp, crab, lobster, clams, oysters, mussels)
- Baby Sunscreen, Mineral (ZnO + TiO2)
- Lead
- Arsenic
- Aluminum
Verification notes
- Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing
wiki/sources/pages before creation. - Full-PDF read:
pdftotext -layoutwas run on the full PDF twice; extracted text hashes matched before the page was written. - Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
- Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
- HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.
Update history
The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.