Table 1

Overview of animal studies with maternal inhalation exposure to whole diesel exhaust
Diesel particulate in air (mg/m3)
 Particle size
 Study type
 Animal species
 Exposure period (GD)
 Maternal measures (n)
 Offspring endpoints (n)
 Ref.
0.3
1.0
3.0
 MMAD 0.4
 T(13)
 M
 2–13
12 h/day
 (23–30)
Implantations
Litter size
Sex ratio
Placentas:
-weight [↑1.0]
-congestion
-abnormal
-inflammatory cytokines [↑0.3, 3.0]
 Fetal weight [↓3.0]
Rate of abnormal fetuses
 [5]
0.3
1.0
3.0
 MMAD 0.4
 P
 M
 From four months before gestation to mating
12 h/day
 (10–12)
Abnormal delivery
Nest construction [↓all]
Weights:
-ovaries
-vagina
-uterus [↓1.0]
 (4–22)
Weight, PND11 [♂↑0.3], 14, 21 [♀↓3.0], 28 [↓3.0], 35 [↓3.0], 42 [↓0.1, 3.0], 49 [↓0.1♂, 3.0], 56 [↓1.0, 3.0], 63 [↓1.0♀, 3.0], 70 [↓3.0]
Vaginal opening [↓0.3, 1.0]
Anogenital distance PND28 [♂↓0.3], 70 [♂↓3.0]
♀ Weights, PND28
-thymus [↓3.0]
-ovary [↓3.0]
♀ Weights, PND70
-adrenals [↓1.0]
-liver [↓1.0]
-thymus [↓0.3, 1.0]
♂ Weights, PND 70
-adrenals [↓1.0]
-testes [↓1.0]
-seminal vesicles [↓1.0]
External malformations
 [4]
0.1
T(13)
 M
 2-3+6-10+13
8 h/day
 (15–16)
Body weight
Implantations
Total placental weight
 (22)
Litter size
Gender ratio
Total fetal weight
Bone morphogenetic protein 15[↓]
 [20]
1.71 or
0.17 (Filtered, pore size estimated to 0.1–0.2 μm)
P
 R
 7–20
6 h/day
 (7–8)
 (7–14)
Gender ratio
Weight, PND 96:
-body
-testis
-epididymis
Daily sperm production [↓]
Spermatids [↓]
Sertoli cells [↓]
Spermatids/Sertoli cell [↓]
FSH [↓]
LH
Testosterone
 [11]
5.6 or
Filtered (pore size 0.05 μm)
 90% < 0.5 μm
 T(20)
 R
 7–20
6 h/day
 (22–24)
Body weight
Implantations
Weights:
-placenta [↓, non-filtered]
-adrenal gland [↓, filtered]
-thymus [↓]
-ovary [↓]
Corpora lutea [smaller]
Testosterone [↑]
Progesterone
Estradiol [↓, filtered]
LH [↓, filtered]
FSH
ACTH
Hydroxycorticosteroids, urinary
 (6–24)
Fetal weight [females↑]
Litter size
Gender ratio
External malformations
Anogenital distance [↑]
Thymus weight [↓]
Testis differentiation [↓]
Ovary differentation [↓]
Thymus differentiation [↓]
 [7]
1.73
or
Filtered (pore size 0.05 μm)
 90% < 0.5 μm
 P
 R
 7-20+
PND 1–3
6 h/day
 (6–7)
 (6–20, males only)
Weight PND 4, 49
Organ weights, PND 4, 49, 82:
-thymus [↓]
-Testosterone, PND 4, 23 [↑]
-Estrogen, PND 4, 23
IgE pollen:
-three immunizations
-four immunizations [↑]
 [9]
6
 ~90% < 1 μ
~50% < 0.3 μ
 T(20)
 R
 5–16
8 h/day
 Resorptions
Implantations
Corpora luetea [↓]
Gross pathology
 Fetal weight
Litter size
Viability
Gender distribution
Malformations
 [6]
6
 ~90% < 1 μ
~50% < 0.3 μ
 T(20)
 Rabbit
 5–16
8 h/day
 (20)
Resorptions
Implantations
Corpora lutea
Gross pathology
 Fetal weight
Litter size
Viability
Gender distribution
Malformations
 [6]
0.3
1.0
3.0
P
 M
 2–16
12 h/day
 (20)
Deaths
 (7–14, males only)
Weight, PND 28 [↑1.0, 3.0]
Gender ratio
Organ weights, PND 28
-testes [↑1.0, 3.0]
-epididymis
-accessory glands [↑1.0, 3.0]
LH
Testosterone [↑1.0]
 [8]
1.0
P
 M
 2–16
24 h/day
 (10)
 (7–10)
Weight, PND 8 [↓], 16(↓), 21(↓), 35 [↓], 84:
-testis
-epididymis
-seminal vesicle [↑, PND8+16]
Sperm counts [↓PND35+84]
Testis morphology [↑Multinucl. cells PND84]
Testosterone [↓PND21,(↓)PND35, ↑PND84]
mRNA, testes:
-androgen receptor
-estrogen receptor
-LH receptor
-FSH receptor
-steroidogen acute regul protein [↑PND84]
-cytochrome P-450 side-chain cleavage
-3βHSD
-17βHSD
-P450c17
-cytochrome P-450 aromatase
 [19]

n: group size. GD: Gestation day. PND: Postnatal day. Study type: P: Postnatal assessment of effects. T(GD): Teratology study, number in brackets designates day of laparatomy. Species: M: Mice. R: Rat. [Square brackets]: indication of dose levels and gender related to exposure associated effect. ↓: decrease; ↑: increase. MMAD: Mass median aerodynamic diameter. LH: Luteinizing hormone. FSH: Follicle stimulating hormone. ACTH: Adrenocorticotropic hormone. HSD: Hydroxysteroid dehydrogenase.

Hougaard et al. Particle and Fibre Toxicology 2008 5:3   doi:10.1186/1743-8977-5-3