Associating the color GREEN with both pig snot and gonorrheal gleet in this glyph caused the entire society of Japan to deny for centuries that the color green even existed, calling it 'blue' instead, until the fundamental meanings of these elements were largely forgotten by the population.
「Loose dripping stinky and sticky threads」that「ooze」and in particular, the GREEN color that snot most famously takes on when a mammal (pig) has a chronic sinus infection (green snot is caused generally by bacteria colonizing the sinuses), or, the GREEN color of discharged gleet during a dose of gonorrhea.
The color green later was applied to GREENERY, as it has in English, perhaps due to use in herbal poultices. Note that「ejaculations of pig sticky liquid」also refers to the same color, since in all likelihood the same infection that has colonized the mucus of the nasal passages will also colonize the mucus of the genitals:「…nevertheless the following viral diseases may be present [in semen], particularly if the boar is ill or at the early acute stage of infection at the time of collection: [viruses listed] Many other viruses have been detected in semen but their significance is not known. Some important bacterial diseases can also be spread in semen during service, notably brucellosis and leptospirosis.」
[ https://www.thepigsite.com/genetics-and-reproduction/insemination/facts-about-semen 2023-05-18 ]
Note that the English words「colony, colonize」etc., refer to the process of bacteria establishing a living space (a settlement) within the large intestine or colon, feeding off the resources (feces) of a host animal, analogous to how some countries have invaded other lands and established settlements in order to feed off the resources of the host territories.
In its most common gaseous state, CHLORINE is yellowish-green and TOXIC, not unlike slimy bacterial infected mucus sometimes found coating the sinuses or glans.
Note that the following colors are all associated with the human body and its various emissions or conditions: black (黒, 黑). Purple (紫). Blue (靑,青). Green (緑,綠). Yellow (黄,黃). Orange (橙). Red (赤). And white (白).

External source definitions …excluding politically incorrect concepts and other meanings deemed offensive today; may include extended definitions, euphemisms, and mnemonics)
Chinese: green
Japanese EDRDG: green, chlorine
Unihan extended: green; chlorine