When you make pig blood more acidic (like adding lemon juice), it grabs onto carbon monoxide gas more easily — but only up to a point. Once it’s super acidic, it doesn’t grab any more gas than before.
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The claim is precise, quantitative, and describes a measurable physiological response in a controlled in vitro system (liquid porcine blood). The effect is based on well-established principles of hemoglobin-oxygen/carbon monoxide binding and the Bohr effect, where lower pH increases hemoglobin’s affinity for CO. The plateau at pH 6.00 is biologically plausible due to saturation of protonation sites on hemoglobin. The language is precise and avoids overgeneralization to humans or in vivo systems.
More Accurate Statement
“At pH 6.70, the carbon monoxide gas concentration required to achieve 100% carboxyhemoglobin saturation in liquid porcine blood is significantly lower than at pH 7.40, but further acidification to pH 6.00 does not produce a statistically significant additional reduction in required gas concentration.”
Context Details
Domain
medicine
Population
animal
Subject
Carbon monoxide saturation of liquid porcine blood
Action
requires less gas to achieve 100% carboxyhemoglobin
Target
at pH 6.70 compared to pH 7.40, with no further reduction at pH 6.00
Intervention Details
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Evidence from Studies
Supporting (1)
Color evaluation of carbon monoxide treated porcine blood
Scientists found that making blood more acidic (lower pH) from normal to a bit more acidic made it easier to saturate with carbon monoxide, but making it even more acidic didn’t help any more — just like the claim said.