Zinc 5-nitroisophthalate

Direct observations: clinical cases, poisoning incidents and other

Administrative data

Endpoint:

direct observations: clinical cases, poisoning incidents and other

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

Not reported

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, meets generally accepted scientific principles, acceptable for assessment

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1984

Materials and methods

Study type:

study with volunteers

Endpoint addressed:

repeated dose toxicity: oral

Principles of method if other than guideline:

A clinical trial was conducted on healthy human volunteers for six weeks to evaluate the effect of the test material on immune response and plasma lipoproteins.

GLP compliance:

no

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material (as cited in study report): Zinc sulfate

Method

Type of population:

general

Subjects:

- Number of subjects exposed: 11
- Sex: Male
- Age: Adult
- Known diseases: None
- Other: Subjects were instructed not to change dietary intake or exercise during the study period

Ethical approval:

not specified

Route of exposure:

oral

Reason of exposure:

intentional

Exposure assessment:

measured

Details on exposure:

Clinical trial: 150 mg Zn (as ZnSO4) was administered to healthy volunteers twice a day for six weeks.

Examinations:

- Haematology: Total number of lymphocytes and function, T and B cells, polymorphonuclear (PMN) leukocyte function, phagocytosis and bactericidal capacity
- Estimation of plasma lipoproteins: Total cholesterol, triglyceride, HDL & LDL-cholesterol
- Estimation of plasma Zn levels by atomic absorption spectrophotometry

Medical treatment:

No

Results and discussion

Clinical signs:

No side effects

Results of examinations:

PLASMA LIPOPROTEINS:
- HDL-cholesterol: Decreased from 42 to 29 mg/dL;
- LDL-cholesterol: Increased from 110 to 127 mg/dL;
- LDL/HDL ratio (atherogenic index): Increased from 2.6 to 4.2
- Total cholesterol and triglyceride levels: No significant change

PLASMA ZINC LEVELS: Increased from 83 to 199 µg/dL

HAEMATOLOGY:
Total lymphocytes count, T and B cells, and T-lymphocyte subsets: No significant change

IMMUNE RESPONSE:
- Polymorphonuclear(PMN) migration response to chemotactic migration: Decreased (292 ± 57 PMN/10 high-power field) during the period of Zinc administration and increased (576 ± 114 PMN/10 high-power field) to baseline values (632 ± 101 PMN/10 high-power field) several weeks after stopping the supplements
- Phagocytosis of opsonized bacteria: Impaired
- Bactericidal capacity: Slightly reduced but not significant

For details see the following tables in the attached PDF:
Table 1: Plasma Zinc Levels and Polymorphonuclear (PMN) Leukocyte Function
Table 2: Lymphocyte Number
Table 3: Serum Lipid and Lipoprotein Concentrations

Effectivity of medical treatment:

Not applicable

Outcome of incidence:

Not applicable

Any other information on results incl. tables

None

Applicant's summary and conclusion

Conclusions:

Under the test conditions, moderately large amount of oral Zinc supplement was observed to be associated with significant impairment of lymphocyte and polymorphonuclear functions.

Executive summary:

A clinical trial was conducted on 14 healthy human volunteers for six weeks to evaluate the effect of the test material (150 mg Zn as ZnSO4, twice a day for six weeks) on immune response and plasma lipoproteins.

 

A reduction in lymphocyte stimulation response to phyto-hemagglutinin as well as chemotaxis and phagocytosis of bacteria by polymorphonuclear leukocytes was observed. Serum high-density lipoprotein concentration decreased significantly and low-density lipoprotein level increased slightly.

 

Under the test conditions, moderately large amount of oral Zinc supplement was observed to be associated with significant impairment of lymphocyte and polymorphonuclear functions.