Uncontaminated

Free from a substance that would make something harmful or impure.

Reach for it when Confirming the safety or purity of water, food, soil, or a sample.

Tests showed that the spring remained uncontaminated after the fuel spill.

• everyday

  clean

  ordinary safety or absence of dirt is enough

  not when does not identify freedom from a specific contaminant

• warm

  pure

  natural or compositional purity matters

  not when can overpromise laboratory-grade purity

• professional

  sanitary

  hygienic conditions are the concern

  not when something sanitary may contain harmless additives

Unaffected by outside material that could distort a result.

Reach for it when Describing evidence, data, or a process protected from unwanted influence.

The sealed control group supplied uncontaminated data for comparison.

• professional

  uncompromised

  evidence retains its intended validity

  not when does not specify the route of possible distortion

• formal

  independent

  a source stands apart from the tested influence

  not when independence alone does not prevent contamination

• literary

  untainted

  outside influence has not spoiled integrity

  not when can carry moral overtones absent from data

• contaminated
• polluted
• compromised

• uncontaminated water

  The filter reserve guaranteed uncontaminated water for the clinic.

• uncontaminated sample

  A technician collected an uncontaminated sample upstream.

• uncontaminated evidence

  Independent storage preserved uncontaminated evidence for the appeal.