Hendrawati et al. 2015 - Chitosan coagulation for lake-water quality

Hendrawati and colleagues tested chitosan prepared from shrimp-shell waste as a natural coagulant for turbid lake water from Situ Cipondoh. This is in-scope mitigation evidence for water treatment and metal reduction, not chitosan ingredient occurrence or aluminum contamination evidence.

Key numbers

The abstract reports that chitosan at 20 ppm lowered lake-water turbidity by 94.43%, lowered pH, decreased bacterial counts by +/- 99.18%, and lowered dissolved Mn, Mg, and Fe in the treated water. The same abstract states that chitosan did not change water temperature, did not lower BOD, and did not lower Ca.

Table 1 describes the untreated Situ Cipondoh water before coagulant addition as 30.17 +/- 0.29 degrees C, pH 8.12 +/- 0.02, conductivity 0.28 +/- 0.00 uS, and turbidity 9.53 +/- 0.01 NTU. The table lists the permitted turbidity limit as 5 NTU and pH range as 6.5-8.5.

Table 12 reports the following treated-water values:

The same table lists maximum values or reference limits for several parameters: turbidity 25 NTU, pH 6.5-9.00, total coliform 50 MPN/100 ml, Mn 0.4 mg/L, Cr 0.05 mg/L, Ca 0.3 mg/L, Fe 0.003 mg/L, and BOD 3 mg/L. These are source-reported comparison values, not HMTc standards.

Methods (brief)

The study prepared chitosan from shrimp shell by deproteinization, demineralization, and deacetylation. Lake water was treated by jar testing: 150 rpm rapid mixing for 10 minutes, 50 rpm slow mixing for 15 minutes, and about 1 hour settling. Supernatant was tested for turbidity, temperature, pH, conductivity, dissolved metals, total coliform, dissolved oxygen, and BOD. Metals were measured by atomic absorption spectrophotometry.

Implications

Certification: Do not use these values as chitosan ingredient occurrence, shellfish waste occurrence, or finished drinking-water occurrence. They are treatment-performance values from a lake-water jar test.

Courses: Useful example of a bio-based coagulant lowering Cr and Mn in surface water while not improving every water-quality parameter; BOD increased in the chitosan-treated sample in Table 12.

App: Context only. The source can support mitigation narrative for chitosan-based water treatment, not consumer-product scoring.

Wiki pages this source may touch

• remediation-evidence
• chromium
• manganese
• iron
• magnesium

Verification notes

Recovered from skip:not-food-occurrence under the 2026-06-10 inclusion-by-default rule. The old skip treated the paper as out of scope because it was a lake-water coagulant study, not product occurrence. On reading, it is in-scope a2 mitigation/remediation because it reports measured water-treatment outcomes and metal concentrations before and after chitosan treatment.

Numbers were checked against the abstract, Table 1, Table 12, methods, and conclusion in the extracted PDF. The narrative text says Mn fell from 0.4381 mg/L to 0.0056 mg/L, while Table 12 prints chitosan-treated Mn as 0.056 mg/L; this page uses the table value and flags the discrepancy. Products and ingredients are intentionally empty.

Page history

The five most recent substantive edits to this page. 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.