Table 1

Participant and household characteristics and surface nicotine and urine data

Characteristic (Measure)Participant
123A3B45
Cigarettes todayNC08301
Wash hands after last cigaretteNCNANoNoNAYes
Wash hands during visitNoNoNoNoNoNo
Smoked while pregnantNoNoYesYesNo
Typical cigarettes per day50*2050*
Days of visitation (out of past 7)NC70177
Day of life/infant hospitalisation†46223455911
Visitation minutes (on study visit)601801409045>180‡
Infant held at visitNoYesYesYesYesYes
Protective gown worn at visitNCNoYesYesNoYes
Protective gloves worn at visitNCNoNoNoNoNo
Number of other household smokers24222
Do other household smokers visitNCYesYesYesYes
Indoor home smoking allowedNoYesYesYesNo
Smoking allowed inside carYesYesNoYesYes
Breastfed infant in past 10 daysNoNoNoNoYesYes
Feeding type at visit§BottleBottleBottleBottleBottle§Breast
Index finger and furniture data
 Index finger nicotine (ng)NC441160496090818
 Crib/incubator (µg/m2)<LOD0.30.2NC0.20.2
 Furniture (µg/m2)0.32.55.534.21.23.4
Infant urine data
 Cotinine (ng/mL) (LOQ=0.05)NC0.170.36NC0.375.01
 3HC (ng/mL) (LOQ=0.1)NC0.630.46NC<LOQ31.58
 NNAL (pg/mL) (LOQ=0.25)NC0.471.64NC1.5812.38
  • Participant 3's visit 1 is labelled as ‘3A’ and visit 2 is labelled as ‘3B’. Participant 1's crib/incubator result was below the LOD (0.1 µg/m2). The incubator measurement was not repeated for participant 3's second measurement (ie, PPT3B).

  • For chairs, the inner material was 90% polyurethane foam and 10% polyester fibre, and the outer upholstery was made of 100% Paloma leather. For couches, the inner material was 100% polyurethane foam, and the outer upholstery was made of 90% vinyl and 10% urethane.

  • *Participants 2 and 5 reported smoking fewer than 1 cigarette a day.

  • †All 5 infants were admitted to the NICU on their date of birth.

  • ‡Participant 5 was rooming with her infant since the infant's admission.

  • §On the day of the assessment, infant participants 1–3 were on bottle-fed formula and participant 5 was breastfed. We did not assess whether the fluid in the bottle was expressed breastmilk or formula for participant 4.

  • Cigarettes Today, Cigarettes smoked on the day of the assessment; Days of Visitation, Number of days visited out of the past 7 days (not including the day of the visit); Feeding Type at Visit, Was the infant bottle fed or breastfed on the day of the assessment; Furniture, A hospital-provided couch or chair. Infant Held at Visit, Did staff observe the participant holding the infant on the day of the assessment; Number of Other Household Smokers, Number of other smokers who live in the household; Protective Gown (or Gloves) Worn at Visit, Did the staff observe the participant wearing protective gowning/gloves on the day of the assessment; Visitation Minutes (on Study Visit), Number of minutes visited on the day of sample collection; Wash Hands after Last Cigarette, On the day of the assessment, did the participant report washing their hands after their most recent cigarette; Wash Hands during Visit, On the day of the assessment, did research staff observe the participant washing their hands.

  • 3HC, trans-3′-hydroxycotinine; LOD, limit-of-detection; LOQ, limit-of-quantification; NA, Not applicable; NC, Not collected; NICU, neonatal ICU; NNAL, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol.